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Language：English   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Mg-Al LDH intercalated PtCl42- anion (PtCl4-LDH) was synthesized by a reconstruction method using potassium tetrachloroplatinate and its thermal changes were investigated at various temperatures. The PtCl4-LDH included 17 mass% Pt was synthesized by a reconstruction method using K2PtCl4 Solution of 10 mM to adjust the pH with NaOH to about 11. The obtained PtCl4-LDH shows high crystallinity and has low content of CO32-. The basal spacing of the obtained PtCl4-LDH was 0.83 nm expanding slightly from 0.78 nm of starting LDH. The XRD patterns of the obtained PtCl4-LDH showed that the second 001 diffraction line (006) became more accentuated than the first one (003) according to the intercalation of Pt components. Pt fine particles in the several nm were directly observed by TEM after firing at 500 degrees C. However, the diffraction patterns of Pt or Pt components were not detected via XRD in the same sample. This is due to the coagulation of Pt components by the narrow basal spacing of the PtCl4-LDH. (C) 2009 The Ceramic Society of Japan, All rights reserved.

DOI： 10.2109/jcersj2.117.1229

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Using solid-state reaction method, Zr2WP2O12 powder was synthesized for this study. The optimum heating condition was 1200 degrees C for 4 h. The obtained powder was compacted and sintered. The relative density of the Zr2WP2O12 ceramics with no sintering additive was 60%. That of samples sintered with more than 0.5 mass% MgO was about 97%. The average grain size (D-50), as estimated from the polished surface of a sample sintered at 1200 degrees C for 4 h was about 1 mu m. The obtained ceramics showed a negative thermal expansion coefficient of about -3.4 x 10(-6) degrees C-1. Young's modulus, Poisson's ratio, three-point bending strength, Vickers microhardness, and fracture toughness of the obtained ceramics were, respectively, 74 GPa, 0.25, 113 +/- 13 MPa, 4.4 GPa and 2.3 Mpa m(1/2). (c) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.materresbull.2009.07.020

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Language：English   Publisher：CHEMICAL SOC JAPAN  

Contact angles were measured for sub-nanoliter-scale droplets of an ionic liquid on an extremely smooth and homogeneous hydrophobic fluoroalkylsilane coating. Subsequently, line tension values were calculated using a new model considering the direction of hydrostatic pressure. The sign of the line tension obtained from this system was negative. Surface hydrophobicity plays an important role in determining the line tension sign.

DOI： 10.1246/cl.2009.1092

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Language：English   Publisher：AMER CHEMICAL SOC  

The evaporation behavior of microliter (2.0 mu L) and subnanoliter (0.8 nL) scale water droplets was investigated on two smooth hydrophobic and hydrophilic fluoroalkylsilane coatings prepared using chemical vapor deposition. The contact angle was constant in the second stage of evaporation for a 2.0 mu L droplet on the hydrophobic coating, but it was slightly decreased in the case of a 0.8 nL droplet. The contact angle decreased gradually in the same stage of evaporation for a 2.0 mu L droplet on the hydrophilic coating, but it was almost constant for a 0.8 nL droplet. These differences in evaporation behavior are expected to originate from the differences of their magnitudes and signs of line tension.

DOI： 10.1021/la902848s

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Mg-Al-ascorbic acid (ASA)-layered double hydroxides (ASA-LDHs) with Mg/Al = 3 were synthesized by ion-exchange, coprecipitation and reconstruction methods. Composites with sodium oleate (SOA)/ASA-LDH were prepared by an ion-exchange method using various concentrations of SOA solutions. The (0 0 3) basal spacing of the ASA-LDHs changed from 0.76 nm in the CO(3)-LDH to 0.78 and 0.86 nm after intercalation of the ASA ions and these basal spacings are in good agreement with models based on the assumption as mono layers and double layers of ASA ions in the LDH interlayers, respectively. The amounts of ASA in the LDHs prepared by the reconstruction method were higher than those by the ion-exchange and coprecipitation methods. In the preparation of composites of SOA/ASA-LDH, an ion-exchange method was more suitable than a reconstruction method to cause surface sorption of the SOA molecules with maintaining intercalated ASA ions in the LDH interlayers. The acid-resistant properties of the composites of SOA/ASA-LDH were found to be much higher than for the pure ASA-LDH and mixture Of CO(3)-LDH and ASA. The surfaces of the LDH particles in the composites are, thus, mostly covered with sorbed SOA molecules and they are good candidates as drug delivery materials for intestines through the stomach. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ijpharm.2009.07.021

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SiO2-TiO2/montmorillonite composites were prepared under acidic. neutral and basic conditions and the solid acidity of the resulting composites were determined. All the SiO2/TiO2. ratio of the colloidal particles was set at 10 but the resulting SiO2/TiO2 ratios were significantly richer in TiO2. The XRD patterns of the acidic composite showed expanding and broadening of the (001) reflection by intercalation of colloidal SiO2-TiO2 particles. but the neutral and basic composites showed only broadening of the reflections and no intercalation. The specific surface areas of the acidic. neutral and basic composites (375, 237 and 247 m(2)/g, respectively) were much larger than of montmorillonite (6 m(2)/g). The average pore sizes were about 4.15 and 50 nm. and the amounts of solid acidic sites measured by the NH3-TPD were 178, 95 and 86 mu mol/g for the acidic. neutral and basic composites, respectively. The solid acid amount of the acidic composite was twice that of a commercial catalyst, K-10, (85 mu mol/g) and much higher than the guest phase SiO2-TiO2 gel (16 mu mol/g) or the host phase montmorillonite (6 mu mol/g). The TPD peak temperatures reflect the acid strength, and were similar in all the samples, ranging from 175 degrees to 200 degrees C. (C) 2009 Elsevier B.V. All rights reserved

DOI： 10.1016/j.clay.2009.08.001

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Keggin ions (PW12O403- (PW12), SiW12O404- (SiW12), H2W12O406- (H2W12)) and TiO2 hybrid thin films were prepared using the layer-by-layer method. Their photocatalytic activities were investigated using gaseous 2-propanol decomposition. All films were transparent in the visible wavelength range. For 2-propanol decomposition, H2W12 was the most effective for the combination with TiO2 despite having the smallest TiO2 deposition amount. The photocatalytic activity of the PW12-TiO2 hybrid film was increased 2.3 times by visible light with UV illumination. This increase was less remarkable for hybrid films of other Keggin ions, suggesting that the visible light excitation of reduced PW12 plays an important role in the enhancement of 2-propanol decomposition. © 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apcata.2009.06.046

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Porous mullite ceramics with unidirectionally oriented pores were prepared by an extrusion method to investigate their capillary rise properties. Rayon fibers 16.5 mu m in diameter and 800 mu m long were used as the pore formers by kneading with alumina powder, kaolin clay, China earthen clay and binder with varying FC(2)O(3) contents of 0, 5 and 7 mass%. The resulting pastes were extruded into cylindrical tubes (outer diameter (OD) 30-50 mm and inner diameter (ID) 20-30 nm), dried at room temperature and fired at 1500 degrees C for 4h. The bulk densities of the resulting porous ceramics ranged from 1.31 to 1.67 g/cm(3), with apparent porosities of 43.2-59.3%. The pore size distributions measured by Hg porosimetry showed a sharp peak at 10.0 mu m in the sample without Fe(2)O(3) and at 15.6 mu m in the samples containing Fe(2)O(3); these pores, which arose from the burnt-out rayon fibers, corresponded to total pore volumes ranging from 0.24 to 0.34 ml/g. SEM showed a microstructure consisting of unidirectionally oriented pores in a porous mullite matrix. Prismatic mullite crystals were well developed on the surfaces of the pore walls owing to the liquid phase formed by the Fe(2)O(3) component added to color the samples. The bending strengths of the tubular samples ranged from 15.6 to 26.3 MPa. The height of capillary rise, measured under controlled relative humidities (RH) of 50, 65 and 85%, was greater in the ceramics containing Fe(2)O(3) than in those without Fe(2)O(3), especially in the thinner samples. The maximum capillary rise reached about 1300 mm, much higher than previously reported. This excellent capillary rise ability is thought to be due to the controlled pore size, pore distribution and pore orientation in these porous mullite ceramics. (C) 2009 Elsevier Ltd. All fights reserved.

DOI： 10.1016/j.jeurceramsoc.2009.03.012

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

SiO2-TiO2/montmorillonite composites with varying SiO2/TiO2 molar ratios were synthesized and the effect of the SiO2/TiO2 ratio on the solid acidity of the resulting composites was investigated. Four composites with SiO2/TiO2 molar ratios of 0. 0.1, 1 and 10 were synthesized by the reaction of colloidal SiO2-TiO2 particles prepared from alkoxides with sodium-montmorillonite at room temperature. The composites showed slight expansion and broadening of the XRD basal reflection. corresponding to the intercalation of fine colloidal SiO2-TiO2 particles into the montmorillonite sheets and incomplete intercalation to form disordered stacking of exfoliated montmorillonite and colloidal SiO2-TiO2 particles. The colloidal particles crystallized to anatase in the low SiO2/TiO2 composites but remained amorphous in the high SiO2/TiO2 composites. The specific surface areas (S-BET) of the composites measured by N-2 adsorption ranged from 250 to 370 m(2)/g, considerably greater than in montmorillonite (6 m(2)/g). The pore size increased with decreasing SiO2/TiO2 molar ratio of the composites. The NH3-TPD spectra of the composites consisted of overlapping peaks, corresponded to temperatures of about 190 and 290 degrees C. The amounts of solid acid obtained from NH3-TPD were 186-338 mu mol/g in the composites: these values are higher than in the commercial catalyst K10 (85 mu mol/g), which is synthesized by acid-treatment of montmorillonite. The present sample with SiO2/TiO2 = 0.1 showed the highest amount of acid, about four times higher than K10. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.materresbull.2009.05.005

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Keggin ions (PW12O403- (PW12), SiW12O404- (SiW12), H2W12O406- (H2W12)) and TiO2 hybrid thin films were prepared using the layer-by-layer method. Their photocatalytic activities were investigated using gaseous 2-propanol decomposition. All films were transparent in the visible wavelength range. For 2-propanol decomposition, H2W12 Was the most effective for the combination with TiO2 despite having the smallest TiO2 deposition amount. The photocatalytic activity of the PW12-TiO2 hybrid film was increased 2.3 times by visible light with UV illumination. This increase was less remarkable for hybrid films of other Keggin ions, suggesting that the visible light excitation of reduced PW12 plays an important role in the enhancement of 2-propanol decomposition. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apcata.2009.06.046

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Fe2O3/Al2O3 powders with a range of Fe/Al compositions were prepared by a gel evaporation method to investigate the effect of alumina on the product phases, magnetic properties and simultaneous adsorption of Ni2+ (a model heavy metal cation), NH4+ (a model eutrophication-related cation) and H2PO4- (a model harmful anion). Precursor gels were prepared by dissolving Fe(NO3)(3)center dot 9H(2)O and AI(NO3)(3)center dot 9H(2)O in ethylene glycol, evaporating to dryness, grinding and heating at 300-1000 degrees C for 5 h. The crystalline products were gamma-Fe2O3 (maghemite), formed at 300-600 degrees C, or alpha-Fe2O3 (hematite) and AlFeO3, formed >600 degrees C. The temperatures of the phase change from gamma-Fe2O3 to alpha-Fe2O3 increased with increasing alumina additions. The resulting lattice parameters suggest that Al3+ is incorporated into these phases up to about 15 mol.% at 300 degrees C, falling to 11 mol.% in the gamma-Fe2O3 formed at 600 degrees C. The alpha-Fe2O3 formed at 700 degrees C contained 6 mol.% Al, increasing to 14 mol.% at 1000 degrees C. The magnetic properties of the samples were measured using a vibrating sample magnetometer. The saturation magnetization values of the gamma-Fe2O3-containing samples increased with the addition of alumina to a maximum value of 61 emu/g in the sample containing 95 mol.% Fe2O3 heated at 400 degrees C. The simultaneous adsorption of Ni2+. NH4+ and H2PO4- from water was investigated by a batch method. The highest adsorption values were found for the sample containing 80 mol.% Fe2O3 heated at 600 degrees C, which contained both gamma-Fe2O3 and alpha-Fe2O3. It was therefore concluded that the addition of alumina to iron oxide affects the crystalline phases and phase changes, and enhances the simultaneous cation and anion uptake ability of the materials. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2009.04.009

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SiO2-TiO2/montmorillonite composites with varying SiO2/TiO2 molar ratios were synthesized and the effect of the SiO2/TiO2 ratio on the solid acidity of the resulting composites was investigated. Four composites with SiO2/TiO2 molar ratios of 0, 0.1, 1 and 10 were synthesized by the reaction of colloidal SiO2-TiO2 particles prepared from alkoxides with sodium-montmorillonite at room temperature. The composites showed slight expansion and broadening of the XRD basal reflection, corresponding to the intercalation of fine colloidal SiO2-TiO2 particles into the montmorillonite sheets and incomplete intercalation to form disordered stacking of exfoliated montmorillonite and colloidal SiO2-TiO2 particles. The colloidal particles crystallized to anatase in the low SiO2/TiO2 composites but remained amorphous in the high SiO2/TiO2 composites. The specific surface areas (SBET) of the composites measured by N2 adsorption ranged from 250 to 370 m2/g, considerably greater than in montmorillonite (6 m2/g). The pore size increased with decreasing SiO2/TiO2 molar ratio of the composites. The NH3-TPD spectra of the composites consisted of overlapping peaks, corresponded to temperatures of about 190 and 290 °C. The amounts of solid acid obtained from NH3-TPD were 186-338 μmol/g in the composites
these values are higher than in the commercial catalyst K10 (85 μmol/g), which is synthesized by acid-treatment of montmorillonite. The present sample with SiO2/TiO2 = 0.1 showed the highest amount of acid, about four times higher than K10. © 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.materresbull.2009.05.005

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Transparent TiO2 nanosheet thin films were prepared using layer-by-layer method with poly(diallyidimethylammonium chloride) as a counter polymer. The possibility of photocatalysis by the light in the long wavelength range was examined by grafting Cu on the film. Photocatalytic decomposition activity for gaseous 2-propanol under UV illumination without light for electron excitation of TiO2 nanosheet was increased by Cu grafting. suggesting that the interfacial charge transfer mechanism is effective also for nanosheet films. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matlet.2009.05.016

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Properties of a solid acid carbon coating prepared on TiO2 powder surface using photochemical vapor deposition (photo-CVD) were evaluated. The TiO2 powder surface became brown during UV illumination under a flowing xylene and xylene sulfonic acid mixture. Observation by TEM revealed an amorphous carbon coating on the TiO2 powder. Sulfonate groups were identified on the coating using FT-IR. A chart of NH3-TPD measurements showed two peaks: that at high temperature was attributed to the coating's strong acid. The carbon coating's acidity was equivalent to that of the solid superacid carbon powder and the carbon-coated TiO2 decomposed cellulose. © 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.catcom.2009.05.006

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Language：English   Publishing type：Rapid communication, short report, research note, etc. (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The repulsive force originating from steric hindrance of polymers in aqueous solvent was investigated using scanning probe microscopy (SPM). The contact angle (CA) of ammonium poly(acrylic acid) (PAA) solution on the Si surface was measured to estimate the state of the Si substrate. Results of CA measurement show that the Si surface was fully covered with PAA at 0.1 mass% in aqueous solution. The interaction force between the Si tip and the wafer was estimated using the SPM force curve mode. The force curve measured in the ion-exchanged purified water showed the typical relation predicted by Derjaguin-Landau-Verway-Overbeek (DLVO) theory. However, the force curve shape in the 0.1 mass% PAA solution was significantly different. Only a repulsive force was observed at less than about 4 nm of separation distance between the Si wafer and cantilever tip. This distance originated from the steric repulsions of PAA adsorbed onto the Si wafer and cantilever tip. Crown Copyright (C) 2009 Published by Elsevier B. V. All rights reserved.

DOI： 10.1016/j.apsusc.2009.06.050

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A series of geopolymers were prepared with varying ratios of sodium silicate, metakaolinite, NaOH and H(2)O and their porous properties, water retention and mechanical properties were determined, to develop materials for counteracting heat island effects. Samples were prepared with the molar ratios SiO(2):Al(2)O(3):Na(2)O:H(2)O of 3.66:1:x:y, where x = 0.92-1.08 and y = 14.2-19.5. The porous and mechanical properties of the geopolymers showed a good correlation with the H(2)O/Al(2)O(3) ratio (y); an increase in y produced an increase in the pore volume (from 0.26 to 0.46 ml/g), the pore size (from 15 to 390 nm) and the water absorption (from 27.2 to 51.1%). The same increase in y decreased the bulk density (from 1.29 to 0.99 g/cm(3)), the bending strength (from 14.2 to <5 MPa) and the water retention. Thus, the H(2)O/Al(2)O(3) ratio is the most important factor for controlling the porous properties of these materials, since geopolymers with higher H(2)O/Al(2)O(3) ratios are more porous and have higher water absorption rates, making them suitable as materials for surface cooling by water evaporation. Geopolymers with lower H(2)O/Al(2)O(3) ratios are more suitable for water retention applications, and have the advantage of higher mechanical strength. (C) 2008 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jeurceramsoc.2008.11.006

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Properties of a solid acid carbon coating prepared on TiO2 powder surface using photochemical vapor deposition (photo-CVD) were evaluated. The TiO2 powder surface became brown during UV illumination under a flowing xylene and xylene sulfonic acid mixture. Observation by TEM revealed an amorphous carbon coating on the TiO2 powder. Sulfonate groups were identified on the coating using FT-IR. A chart of NH3-TPD measurements showed two peaks: that at high temperature was attributed to the coating's strong acid. The carbon coating's acidity was equivalent to that of the solid superacid carbon powder and the carbon-coated TiO2 decomposed cellulose. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.catcom.2009.05.006

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Language：English   Publisher：CHEMICAL SOC JAPAN  

Line tension was measured for microliter-scale and subnanoliter-scale droplets of an ionic liquid on a highly smooth and homogeneous fluoroalkylsilane coating. Values for microliter-scale droplets were two orders larger than those for subnanoliter-scale droplets despite their identical combinations of solid surfaces and liquid. Scale factors related to this measurement and hydrostatic pressure from the liquid play an important role in the discrepancy.

DOI： 10.1246/cl.2009.580

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TiO2/montmorillonite composites were prepared by reaction of montmorillonite with a TiO2 Sol formed by hydrolyzing titanium iso-propoxide, at 50-80 degrees C. The composites showed expanding and broadening of the basal reflections of montmorillonite indicating a partial intercalation of the smaller colloidal TiO2 particles and increased disorder. The reaction temperature affected largely the amount of TiO2 hydrolyzed and the resulting pore sizes. Both properties increased with increasing reaction temperature: the TiO2 content from 24.2 to 46.6 mass% and the average pore size from 2 to 20 nm. The colloidal TiO2 particles consisted of anatase up to 1000 degrees C without transforming into rutile. The growth of the TiO2 particles was suppressed by the montmorillonite particles. Adsorption of methylene blue (MB) was higher in the composite prepared at 80 degrees C than in that at 50 degrees C because of the larger pore size. Photocatalytic decomposition of 1,4-dioxane by the composites was higher than for pure anatase due to the synergy effect of adsorption for 1,4-dioxane and photodecomposed intermediates by montmorillonite and its photodecomposition by TiO2. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.clay.2009.03.005

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Language：English   Publisher：AMER CHEMICAL SOC  

Evaporation and sliding behaviors of water droplets were investigated on smooth and rough fluoroalkylsilane coatings. The rough coating possesses nanoscale roughness and chemical heterogeneity on its surface. Evaporation behaviors for these two coatings differed when nanoliter-scale droplets were used, although they were nearly identical for rnicroliter-scale droplets. The droplets on the smooth coating exhibit greater sliding acceleration and a larger slipping velocity ratio than those on the rough coating. Both the evaporation behavior of nanoliter-scale droplets and sliding velocity of microliter-scale droplets were affected by nanoscale surface heterogeneity. They are indicators for highly homogeneous smooth silane coatings.

DOI： 10.1021/la8040665

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Anatase polycrystalline thin films and a plasma crystallization process were used to investigate the dependence of the photoinduced friction force variation for a TiO2 Surface on the UV intensity and atmosphere. Photoinduced friction force variation for UV illumination time was divisible into two stages, decreasing and increasing, where the switching time between these two stages and the degree of variation depended oil the UV intensity and atmosphere. The decreasing stage was attributable to the photocaralytic decomposition of organic compound adsorbed onto the Surface, whereas the increasing stage was attributed to the capillary effect or an increase in the adsorbed water layer. Results demonstrated that UV intensity and atmosphere controlled the friction force. (C) 2009 Elsevier B.V. All lights reserved.

DOI： 10.1016/j.jphotochem.2009.01.009

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We investigated nanoscale surface modifications of silicate glass plates by applying a thermal nanoimprint technique, in which self-organized nanopattern molds of sapphire (alpha-Al2O3 single crystal) wafer were used. Nanopatterns of the sapphire mold exhibited regularly arranged straight atomic-steps with a uniform height of 0.2 nm and atomically flat terraces about 80 run in width. We succeeded in forming subnanometer-stepped surfaces of glass. By pressing the glass plate over the mold and then slowly cooling (3 degrees C/min), a three-dimensional nanostriped pattern (periodic distance of 60-85 nm and peak-to-valley height of 8 nm) was obtained on the glass plate. Softening behavior of the nanopatterned glass morphology was observed at temperatures about 20 degrees C lower than the glass transition temperature of the bulk glass. The Vickers hardness of the nanostriped glass was estimated to be higher than that of non-patterned glass, and the surface of the nanostriped glass was more hydrophobic than that of non-patterned glass. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.mseb.2009.01.01

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Porous ceramics were prepared by firing mixtures of talc (Mg(3)Si(4)O(10)(OH)(2)) and foamed glass particles (ceramic balloons, CB) with and without LiCl as a sintering acid. The mixing ratios of the starting materials were talc:CB = 7:3, 8:2, 9:1 and 10:0, with additions of LiCl of 0, 2 and 5 mass%. The mixtures were formed into pellets and fired at 600-1000 degrees C. The pellets without LiCl showed very poor strength even when fired at 1000 degrees C but those containing LiCl were much stronger, even when fired at only 600 degrees C. The crystalline phases in these samples changed to enstatite (MgSiO(3)) at >= 700 degrees C by decomposition of the talc under the fluxing action of the LiCl. The resulting samples were machinable and easily cut and drilled. The cutting rate decreased with increasing bending strength, for example, from 105 mm(2)/s and 6.3 MPa to 50 mm(2)/s and 16.3 MPa, respectively. The drilling rate of the present sample was found to be only slightly less than Teflon (polytetrafluoroethylene, PTFE) but much faster than graphite, glass ceramics, etc. (C) 2008 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jeurceramsoc.2008.07.055

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A super-hydrophobic coating was prepared by combining a rigid base film with crater-like hemispherical holes and acicular nanoparticles. The acicular boehmite powder provides a high contact angle on the film surface. The rigid base film with crater-like hemispherical holes inhibits the rapid decrease of contact angle by surface rubbing. The combination of different roughness is an effective method for improving the abrasion resistance of super-hydrophobic films. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.mseb.2008.11.016

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CaSiO3/high-density polyethylene (HDPE) composites with flexibility and biocompatibility were prepared by a new surface loading method. CaSiO3 powder was synthesized by coprecipitation method with heating at 1300 degrees C for 2 h. The obtained alpha-CaSiO3 powder was sieved to 45-75 mu m (sample M) and 75-150 mu m (sample C). Fine powder sample (sample F) was prepared by grinding the powder being the average particle size of 2.9 mu m. These powders were sprinkled on the melted HDPE sheets heated at 160, 180 and 200 degrees C. The amounts of sprinkled powder were only <0.1 vol.% but the ratios of surface coverage area were >50% in all the samples. Apatite formation in simulated body fluid (SBF) was observed by soaking for 5 days in sample F while within 1 day in samples M and C. The sample M retained flexible properties of HDPE together with excellent biocompatible properties. (C) 2008 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.materresbull.2008.06.011

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Using continuous coating with Si-alkoxide as a binder, Cs2.5H0.5PW12O40 (Cs2.5) powder was prepared and immobilized onto a Pyrex glass plate. The Cs2.5 coating possessed an acid site on the film surface. Translucent TiO2-Cs2.5 hybrid films were prepared by laminating TiO2 films with holes on the Cs2.5 coating using phase-separation of alkoxide. Photocatalytic decomposition of 1,4-dioxane in water revealed that the holes serve as adsorption fields for ethylene glycol diformate, an intermediate with poor affinity to TiO2. The TiO2-Cs2.5 hybrid films produced by this process are candidates for purification of water containing several chemicals with a slow decomposition rate in photocatalysis. © 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.surfcoat.2008.10.010

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Using a laser beam and its reflection, we evaluated surface air layers on two superhydrophobic coatings with different roughnesses (R(a) = 1900 and 74 nm) in a water-ethanol mixture. The reflected laser intensity decreased by increasing the ethanol concentration for the superhydrophobic coating with large roughness because of increased scattering by the surface structure of the solid. However, it was almost constant and slightly increased for the coating with small roughness, probably because the liquid-air interface becomes flatter as the liquid intrudes into the surface structure. Results demonstrated that the difference in surface structure provides different sustainability of the surface air layer.

DOI： 10.1021/la802763h

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Using continuous coating with Si-alkoxide as a binder, Cs2.5H0.5PW12O40 (Cs2.5) powder was prepared and immobilized onto a Pyrex glass plate. The Cs2.5 coating possessed an acid site on the film surface. Translucent TiO2-Cs2.5 hybrid films were prepared by laminating TiO2 films with holes on the Cs2.5 coating using phase-separation of alkoxide. Photocatalytic decomposition of 1,4-dioxane in water revealed that the holes serve as adsorption fields for ethylene glycol diformate, an intermediate with poor affinity to TiO2. The TiO2-Cs2.5 hybrid films produced by this process are candidates for purification of water containing several chemicals with a slow decomposition rate in photocatalysis. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.surfcoat.2008.10.010

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DOI： 10.11362/jcssjclayscience.14.2_87

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This study investigated the effect of surface roughness on a coating of TiO2 submicron powders that had been applied on a stainless steel mesh using electrophoretic deposition (EPD). Roughness was provided to the surface of EPD coating using UV pre-illumination to the suspension prepared by isopropyl alcohol and commercial TiO2 powder. The Ra value was increased around 20% by this treatment. The rough coating provided a higher photocatalytic decomposition rate of 1,4-dioxane in water than a smooth coating obtained from the suspension without UV pre-illumination. That increase is attributable to the increase of the reaction field on the coating surface.

DOI： 10.4028/www.scientific.net/KEM.412.137

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DOI： 10.4139/sfj.59.907

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DOI： 10.4011/shikizai.82.3

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DOI： 10.1016/j.apcata.2009.06.046

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DOI： 10.4011/shikizai.82.3

CiNii Books

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DOI： 10.4139/sfj.59.907

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DOI： 10.11362/jcssjclayscience.14.2_87

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Language：English   Publisher：Ceramic Society of Japan  

Mg-Al LDH intercalated PtCL4 2- anion (PtCl 4-LDH) was synthesized by a reconstruction method using potassium tetrachloroplatinate and its thermal changes were investigated at various temperatures. The PtCl4-LDH included 17 mass% Pt was synthesized by a reconstruction method using K2PtCl4 solution of 10 mM to adjust the pH with NaOH to about 11. The obtained PtCl4-LDH shows high crystallinity and has low content of CO3 2-. The basal spacing of the obtained PtCl4-LDH was 0.83 nm expanding slightly from 0.78 nm of starting LDH. The XRD patterns of the obtained PtCl 4-LDH showed that the second 001 diffraction line (006) became more accentuated than the first one (003) according to the intercalation of Pt components. Pt fine particles in the several nm were directly observed by TEM after firing at 500°C. However, the diffraction patterns of Pt or Pt components were not detected via XRD in the same sample. This is due to the coagulation of Pt components by the narrow basal spacing of the PtCl4-LDH. ©2009 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.117.1229

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DOI： 10.4139/sfj.60.2

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Language：English  

This study investigated the effect of surface roughness on a coating of TiO2 submicron powders that had been applied on a stainless steel mesh using electrophoretic deposition (EPD). Roughness was provided to the surface of EPD coating using UV pre-illumination to the suspension prepared by isopropyl alcohol and commercial TiO2 powder. The Ra value was increased around 20% by this treatment. The rough coating provided a higher photocatalytic decomposition rate of 1,4-dioxane in water than a smooth coating obtained from the suspension without UV pre-illumination. That increase is attributable to the increase of the reaction field on the coating surface.

DOI： 10.4028/www.scientific.net/KEM.412.137

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Language：English   Publisher：TRANS TECH PUBLICATIONS LTD  

This study investigated the effect of surface roughness on a coating of TiO(2) submicron powders that had been applied on a stainless steel mesh using electrophoretic deposition (EPD). Roughness was provided to the surface of EPD coating using UV pre-illumination to the suspension prepared by isopropyl alcohol and commercial TiO(2) powder. The R(a) value was increased around 20% by this treatment. The rough coating provided a higher photocatalytic decomposition rate of 1,4-dioxane in water than a smooth coating obtained from the suspension without UV pre-illumination. That increase is attributable to the increase of the reaction field on the coating surface.

DOI： 10.4028/www.scientific.net/KEM.412.137

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Si plates were treated using two fluoroalkylsilanes (FAS17 and FAS3), and the internal fluidity of a water droplet sliding between two parallel plates on a slope was observed directly using particle image velocimetry (PIV) method with a high-speed camera system. The interfacial caterpillar-like rotation flows with slip motion at the solid-liquid interface were related to the combination of top and bottom wettabilities. The water droplets accelerated by a rolling and slipping motion on FAS17 coatings; the acceleration was dominated by a rolling motion on FAS3 coatings. A droplet's shape, solid-liquid molecular interaction, and the gravitic force will be important factors determining the sliding mode on a solid surface. (C) 2008 Elsevier B. V. All rights reserved.

DOI： 10.1016/j.apsusc.2008.09.059

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Si plates were treated using two fluoroalkylsilanes (FAS17 and FAS3), and the internal fluidity of a water droplet sliding between two parallel plates on a slope was observed directly using particle image velocimetry (PIV) method with a high-speed camera system. The interfacial caterpillar-like rotation flows with slip motion at the solid-liquid interface were related to the combination of top and bottom wettabilities. The water droplets accelerated by a rolling and slipping motion on FAS17 coatings; the acceleration was dominated by a rolling motion on FAS3 coatings. A droplet's shape, solid-liquid molecular interaction, and the gravitic force will be important factors determining the sliding mode on a solid surface. (C) 2008 Elsevier B. V. All rights reserved.

DOI： 10.1016/j.apsusc.2008.09.059

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Mesoporous silicas (MesoPSs) were hydrothermally synthesized from calcined and selectively acid-leached kaolinites with a range of crystallinity, using cetyltrimethyl ammonium bromide (CTABr), to investigate the effect of the kaolinite crystallinity on the porous properties of the resulting MesoPSs. Four kaolinites were used, with Hinckley indices ranging from 0.51 to 1.20 and (001) crystallite sizes ranging from 20 to 37 nm. After calcination at 600 degrees C for 24 h they were selectively leached with 2.5 M H(2)SO(4) at 90 degrees C for 2 h to prepare microporous silica (MicroPSs). The Si/Al ratios of these MicroPSs varied from 21 to 82 and their specific surface areas (S(BET)) ranged from 169 to 370 m(2)/g, these parameters tending to increase with decreasing Hinckley index of the kaolinite. MesoPSs were synthesized by reacting the resulting MicroPSs with CTABr in NaOH solution under hydrothermal conditions. The MicroPS was mixed with CTABr, NaOH and water in the molar ratio (MicroPS):CTABr:NaOH:H(2)O = 1:0.1:0.3:150. The synthesis was carried out by stirring the suspension at room temperature for 24 h, aging for 24 h, hydrothermal treatment at 110 degrees C for 24 h and calcination at 560 degrees C for 6 h to remove the surfactants. The S(BET) values of the resulting MesoPSs ranged from 932 to 1240 m(2)/g, correlating with the S(BET) values of the precursor MicroPS and the crystallinity of the kaolinite starting materials. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.clay.2007.09.009

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Mesoporous silicas (MesoPSs) were hydrothermally synthesized from calcined and selectively acid-leached kaolinites with a range of crystallinity, using cetyltrimethyl ammonium bromide (CTABr), to investigate the effect of the kaolinite crystallinity on the porous properties of the resulting MesoPSs. Four kaolinites were used, with Hinckley indices ranging from 0.51 to 1.20 and (001) crystallite sizes ranging from 20 to 37 nm. After calcination at 600 degrees C for 24 h they were selectively leached with 2.5 M H(2)SO(4) at 90 degrees C for 2 h to prepare microporous silica (MicroPSs). The Si/Al ratios of these MicroPSs varied from 21 to 82 and their specific surface areas (S(BET)) ranged from 169 to 370 m(2)/g, these parameters tending to increase with decreasing Hinckley index of the kaolinite. MesoPSs were synthesized by reacting the resulting MicroPSs with CTABr in NaOH solution under hydrothermal conditions. The MicroPS was mixed with CTABr, NaOH and water in the molar ratio (MicroPS):CTABr:NaOH:H(2)O = 1:0.1:0.3:150. The synthesis was carried out by stirring the suspension at room temperature for 24 h, aging for 24 h, hydrothermal treatment at 110 degrees C for 24 h and calcination at 560 degrees C for 6 h to remove the surfactants. The S(BET) values of the resulting MesoPSs ranged from 932 to 1240 m(2)/g, correlating with the S(BET) values of the precursor MicroPS and the crystallinity of the kaolinite starting materials. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.clay.2007.09.009

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Steel-making slag, a waste by-product of the Steel Industry, constitutes a major disposal problem. In the present study, excellent adsorbent materials for reducing eutrophication in wastewaters have been prepared from this slag. Heated samples of acid-treated slag and mixtures of slag with kaolinite and Al(OH)(3) were examined to determine their uptake capacities for NH4+ and PO43- from aqueous solutions. In general, the equilibrium pH of the solution increased in comparison to initial pH with the uptake of target ions, the sample activated slag-Al(OH)(3) showing the smallest change. The highest PO43- uptake capacity was obtained with the slag-Al(OH)(3) mixture heated at 900 degrees C whereas the highest uptake of NH4+ was found in the slag-Al(OH)(3) mixture heated at 800 degrees C. The uptake rates for PO43- and NH4+ by the slag-Al(OH)(3) mixture heated at 900 degrees C were 2.91 and 0.65 mu mol/(g min), respectively. It was shown that heating slag composites prior to incorporation into wastewater treatment filters resulted in an increased degree of NH4+ and PO43- uptake. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2007.12.009

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Language：English   Publisher：ELSEVIER SCIENCE SA  

For this study, transparent sulfated TiO(2) thin films were prepared from Ti alkoxide. Vacuum ultraviolet illumination in air at 180 degrees C was demonstrated to be an effective pretreatment for reproducible preparation of crack-free sulfated TiO(2) thin films. The film provides a high photoinduced wettability conversion rate and photocatalytic decomposition efficiency on gaseous n-hexane under proper conditions. This result is attributable to the accelerated decomposition of intermediates by a strong inorganic acid on the surface or to the resultant high quantum yield by suppressing the recombination between electrons and holes on the film surface. (c) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.tsf.2007.12.161

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Language：English   Publisher：ELSEVIER SCIENCE SA  

For this study, transparent sulfated TiO(2) thin films were prepared from Ti alkoxide. Vacuum ultraviolet illumination in air at 180 degrees C was demonstrated to be an effective pretreatment for reproducible preparation of crack-free sulfated TiO(2) thin films. The film provides a high photoinduced wettability conversion rate and photocatalytic decomposition efficiency on gaseous n-hexane under proper conditions. This result is attributable to the accelerated decomposition of intermediates by a strong inorganic acid on the surface or to the resultant high quantum yield by suppressing the recombination between electrons and holes on the film surface. (c) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.tsf.2007.12.161

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Language：English   Publisher：CHEMICAL SOC JAPAN  

The effect of liquid viscosity on the internal fluidity of droplets during sliding on an inclined Si surface treated with fluoroalkylsilane (FAS) was investigated for water-glycerin mixture using particle image velocimetry (PIV). Increasing viscosity remarkably decreases the slipping motion on the solid-liquid interface and overall sliding acceleration. It affects the rolling motion, but its degree of influence is smaller than that on slipping. The viscosity had different contributions to slipping and rolling motions of the droplets.

DOI： 10.1246/cl.2008.688

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Language：English   Publisher：CHEMICAL SOC JAPAN  

The effect of liquid viscosity on the internal fluidity of droplets during sliding on an inclined Si surface treated with fluoroalkylsilane (FAS) was investigated for water-glycerin mixture using particle image velocimetry (PIV). Increasing viscosity remarkably decreases the slipping motion on the solid-liquid interface and overall sliding acceleration. It affects the rolling motion, but its degree of influence is smaller than that on slipping. The viscosity had different contributions to slipping and rolling motions of the droplets.

DOI： 10.1246/cl.2008.688

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Language：English   Publisher：AMER CHEMICAL SOC  

Using the layer-by-layer method, 12 tungsto(VI) phosphoric acid (PW(12)) and TiO(2) hybrid thin films were prepared. In 2-propanol decomposition, two-bilayer thin films (ca. 15 nm) showed more rapid decomposition than control TiO(2) and PW(12) films under both UV and Visible light illumination. Visible light illumination was required for continuous 2-propanol decomposition. Photocatalytic decomposition activity depends on the number of bilayer coatings, the top coating, and the organic compounds for decomposition. On the basis of the wavelength dependence of the hybrid thin films, a reaction scheme for this system was discussed.

DOI： 10.1021/cm800167x

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Language：English   Publisher：AMER CHEMICAL SOC  

Using the layer-by-layer method, 12 tungsto(VI) phosphoric acid (PW(12)) and TiO(2) hybrid thin films were prepared. In 2-propanol decomposition, two-bilayer thin films (ca. 15 nm) showed more rapid decomposition than control TiO(2) and PW(12) films under both UV and Visible light illumination. Visible light illumination was required for continuous 2-propanol decomposition. Photocatalytic decomposition activity depends on the number of bilayer coatings, the top coating, and the organic compounds for decomposition. On the basis of the wavelength dependence of the hybrid thin films, a reaction scheme for this system was discussed.

DOI： 10.1021/cm800167x

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Language：English   Publisher：ELSEVIER SCI LTD  

Porous ceramics for anti-heat island effect were prepared from mixtures of allophane and vermiculite (VA samples). Allophane and vermiculite which had been ground for 0.5-2 h was mixed in various mass ratios, formed into pellets by uniaxial pressing at 40 MPa, and heated at 600-800 degrees C to form porous ceramics. The large thermal expansion of the vermiculite upon explosive dehydration of interlayer water causes cracking of the pellets with higher vermiculite contents. However, this can be controlled by grinding the vermiculite prior to heating. Grinding the vermiculite for >= 2 It suppresses its expansion, enabling pellet samples with high vermiculite contents to be prepared without cracking. The bulk densities of samples prepared at 800 degrees C from vermiculite ground for 2 h decrease from 1.72 to 0.94 with increasing allophane content. The pore size distribution in these samples shows a distinct peak at about 1 mu m irrespective of the mixing ratio. The number of smaller pores (50 nm) increases with increasing allophane content while the number of larger pores (20-40 mu m) increases with increasing vermiculite content. The compressive strengths of the samples range from I to 3 MPa except for samples containing a high proportion of vermiculite ground for I h. The water absorption (W-a) of the samples increases from 37 to 63% with increasing allophane content. This absorption rate is fast enough to absorb >90% of the W-a within 1 min for samples of 10 mm phi x 5 mm(3) size. By contrast, the release of the absorbed water is very slow, with 50% of the W-a retained for >= 30 h in the VA samples at a relative humidity of 55% at 20 degrees C this is slower than in pure allophane and much slower than in a reference sample of foamed glass (about 4 h). All these properties make the VA samples useful as water-retaining materials to combat "heat island" effects. (c) 2006 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

DOI： 10.1016/j.ceramint.2006.10.006

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Variations of friction force and surface potential were evaluated using friction force microscopy (FFM) and Kelvin force microscopy (KFM) on (100) and (001) faces of rutile single crystals under UV illumination in three different atmospheres: dry nitrogen, dry air, and ambient air. Friction force and surface roughness for the (100) face did not exhibit remarkable dependence on either UV illumination or on the atmosphere. However, the friction force of the (001) face increased by UV illumination in dry air without roughness variation. The surface potential of the (001) face changed negatively and more remarkably than that of the (100) face by UV illumination. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matlet.2007.08.036

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Three materials were prepared from paper sludge (PS) using different treatment processes and their sorption abilities for phosphate and methylene blue (MB) were determined. The samples were a powder sample prepared by heating PS in air (sample C), a pellet prepared by grinding, forming and heating PS in air (sample G) and a powder prepared by physical activation of PS in flowing wet nitrogen (sample A). The three samples were heated at 600-900 degrees C for 6h. On heating at 700-800 degrees C, the organic fibers, limestone (CaCO3) kaolinite (Al2Si2O5(OH)(4)) and talc (Mg3Si4O10(OH)(2)) in the original PS were converted to amorphous CaO-Al2O3-SiO2 (CAS) and talc in sample C, while CAS was formed in sample G and activated carbon, CAS and talc was formed in sample A. On heating at 900 degrees C the CAS converted to gehlenite (Ca2Al2SiO7) and anorthite (CaAl2Si2O8). The specific surface areas (SBET) of the three samples achieved maximum values of 23, 37 and 70 m(2)/g upon heating at 700, 600 and 600 degrees C, respectively. The SBET value of the activated sample A was distinctly lower than usually reported for activated carbon. The samples C, G and A achieved maximum phosphate sorption capacities of 2.04, 1.38 and 1.70 mmol/g, calculated from the Langmuir model, upon heating at 700, 700 and 800 C, respectively. The maximum sorption capacity for phosphate in sample C is attributed to the sorption by CAS, namely, adsorption on the alumina component and precipitation as Ca-phosphates. The MB multifunctional sorption capacity of sample A was 0.11 mmol/g. The phosphate and MB sorption rates show better correlation with a pseudo-second order model than with other models. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2007.06.058

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Variations of friction force and surface potential were evaluated using friction force microscopy (FFM) and Kelvin force microscopy (KFM) on (100) and (001) faces of rutile single crystals under UV illumination in three different atmospheres: dry nitrogen, dry air, and ambient air. Friction force and surface roughness for the (100) face did not exhibit remarkable dependence on either UV illumination or on the atmosphere. However, the friction force of the (001) face increased by UV illumination in dry air without roughness variation. The surface potential of the (001) face changed negatively and more remarkably than that of the (100) face by UV illumination. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matlet.2007.08.036

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Language：English   Publisher：CHEMICAL SOC JAPAN  

The effect of surface roughness on the internal fluidity of a water droplet during sliding on an inclined Si surface treated fluoroalkylsilane (FAS) was investigated using particle image velocimetry (PIV). A water droplet slid down by caterpillar-like rotation flow with or without slippage on the solid-liquid interface. The slipping/rolling ratio on the sliding acceleration depended on the surface roughness; the droplet advanced on the rough surface mainly by the rolling mechanism.

DOI： 10.1246/cl.2008.58

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Language：English   Publisher：ELSEVIER SCIENCE BV  

We prepared line-patterned hydrophobic surfaces using fluoroalkylsilane (FAS) and octadecyltrimethoxysilane (ODS) then investigated the effect of line direction on sliding behavior of water droplets by direct observation of the actual droplet motion during sliding. Water droplets slide down with a periodic large deformation of the contact line and sliding velocity fluctuation that occurred when they crossed over the 500-mu m ODS line regions in FAS regions on a Si surface tilted at 35 degrees. These behaviors are less marked for motion on a 100-mu m line surface, or on lines oriented parallel to the slope direction. Smaller droplets slide down with greater displacement in the line direction on 500-mu m line patterning when the lines were rotated at 13 degrees in-plane for the slope direction. This sliding behavior depended on the droplet size and rotation angle, and is accountable by the balance between gravitational and retentive forces. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apsusc.2007.07.171

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DOI： 10.2109/jcersj2.116.181

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Language：Japanese   Publisher：公益社団法人 日本化学会  

酸化チタン(TiO_2)は間欠的な紫外光照射さえあれば,水に極めて濡れやすい表面状態が繰り返し発現されることから,今日様々な工業分野で幅広く利用されている。本稿では固体の濡れを制御する表面機能材料として,酸化チタンの光誘起超親水性について紹介する。

DOI： 10.20665/kakyoshi.56.9_436

CiNii Books

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DOI： 10.2109/jcersj2.116.187

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Language：Japanese   Publisher：日本塗装技術協会  

CiNii Books

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DOI： 10.2109/jcersj2.116.181

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DOI： 10.2109/jcersj2.116.187

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Language：Japanese   Publisher：Japan Society of Colour Material  

DOI： 10.4011/shikizai.81.348

CiNii Books

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Language：English  

TiO3 powders were prepared by acid treatment of BaTiO3 and their properties were investigated. The BaTiO3 powder was subjected to HNO3 in concentrations ranging from 10-3 to 8 M at 90 °C for 0.5-6 h. Dissolution of BaTiO3 and precipitation of TiO2 occurred at acid concentrations of 2-5 M. BaTiO3 dissolves completely to form a clear solution at reaction times of 0.5-1 h, but a rutile precipitate is formed after 2 h of acid treatment. By contrast, anatase is precipitated by adjusting the pH of the clear solution to 2-3 using NaOH or NH4OH solution. The rutile crystals were small and rod-shaped, consisting of many small coherent domains connected by grain boundaries with small inclination angles and edge dislocations, giving them a high specific surface area (SBET). With increasing HNO3 concentration, the SBET value increased from 100 to 170 m2/g while the crystallite size decreased from 25 to 11 nm. The anatase crystals obtained here were very small equi-axial particles with a smaller crystallite size than the rutile and SBET values of about 270 m2/g (higher than the rutile samples). The photocatalytic activity of these TiO2 was determined from the decomposition rate of Methylene Blue under ultraviolet irradiation. Higher decomposition rates were obtained with larger crystallite sizes resulting from heat treatment. The maximum decomposition rates were obtained in samples heated at 500-600 °C. The photocatalytic activity of the TiO2 was found to depend more strongly on the sample crystallite size than on SBET. © 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.materresbull.2006.12.011

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

TiO3 powders were prepared by acid treatment of BaTiO3 and their properties were investigated. The BaTiO3 powder was subjected to HNO3 in concentrations ranging from 10(-3) to 8 M at 90 degrees C for 0.5-6 h. Dissolution of BaTiO3 and precipitation of TiO2 occurred at acid concentrations of 2-5 M. BaTiO3 dissolves completely to form a clear solution at reaction times of 0.5-1 h, but a rutile precipitate is formed after 2 h of acid treatment. By contrast, anatase is precipitated by adjusting the pH of the clear solution to 2-3 using NaOH or NH4OH solution. The rutile crystals were small and rod-shaped, consisting of many small coherent domains connected by grain boundaries with small inclination angles and edge dislocations, giving them a high specific surface area (S-BET). With increasing HNO3 concentration, the SBET value increased from 100 to 170 m(2)/g while the crystallite size decreased from 25 to 11 nm. The anatase crystals obtained here were very small equi-axial particles with a smaller crystallite size than the rutile and S-BET values of about 270 m(2)/g (higher than the rutile samples). The photocatalytic activity of these TiO3 was determined from the decomposition rate of Methylene Blue under ultraviolet irradiation. Higher decomposition rates were obtained with larger crystallite sizes resulting from heat treatment. The maximum decomposition rates were obtained in samples heated at 500-600 degrees C. The photocatalytic activity of the TiO3 was found to depend more strongly on the sample crystallite size than on S-BET. (C) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.materresbull.2006.12.011

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Language：English   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

Mesoporous silicas were synthesized by hydrothermal treatment of selectively acid-treated saponite (an ideal structural formula: Na1/3Mg3-(Si11/3Al1/3)O-10(OH)(2)), having a 2:1 type layered structure as the silica source and its porous properties were examined and compared with that from kaolinite (an ideal structural formula: Al2Si2O5(OH)(4)), having a 1:1 type layered structure. Synthetic saponite was selectively leached in H2SO4 solutions with various concentrations (0.05-1 M) at 70 degrees C for 0.5 h. The resulting products (precursors) were mixed with cetyltrimethylammonium bromide (CTABr), NaOH and H2O, hydrothermally treated at 110 degrees C and removed the CTABr by calcining at 560 degrees C. A hexagonal mesoporous phase was obtained with higher Si/(Al(+Mg)) ratios of the resulting precursors. The XRD patterns of these products show the peaks assigned by a hexagonal lattice with a(0) = 4.0-4.6 nm and the crystatlinity becomes higher with higher Si/(Al(+Mg)) ratios of the precursors. The specific surface area (S-BET) values of the present mesoporous silicas range from 800 to 1100 m(2)/g at CTABr/precursor = 0.1 and although they are not as high as those from precursors prepared from calcining and acid-treatment of kaolinite (1420 m(2)/g), they are increased to 14001500 m2/g by increasing the ratio CTABr/precursor >= 0.2. The reason for the difference in the optimum preparation conditions between saponite and kaolinite may be attributed to the difference in the linkage of the SiO4 tetrahedra in these precursors (i.e. layered or framework structures), which result in great differences in the selective leaching rates and structures of the resulting silica-rich products. (c) 2007 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2007.05.036

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Language：English   Publisher：ELSEVIER SCIENCE BV  

The freezing behavior of a supercooled water droplet on a silicon surface treated with using various silanes was observed directly using a high-speed camera system. Freezing stability is best ensured by heterogeneous nucleation from a three-phase (solid-liquid-air)- contact line. Differential scanning calorimetry measurements revealed that the freezing temperature of a supercooled water droplet on a fluoro-alkylsilane monolayer was lower than that of alkylsilane. Interaction between the fluorocarbon and water molecule, in addition to structural characteristics of silanes, might play an important role in the heterogeneous nucleation of supercooled water. (C) 2007 Published by Elsevier B.V.

DOI： 10.1016/j.cplett.2007.07.066

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Language：English   Publisher：AMER CHEMICAL SOC  

Smooth (Ra approximate to 0. 1 nm) and rough (Ra approximate to 20 nm) coatings of 1H, 1H,2H,2H-perfluorodecyltrimethoxysilane (FAS17) were prepared by controlling process conditions. The water contact angles for the smooth and rough coatings were similar (107 degrees and 110 degrees, respectively), but their sliding angles differed considerably (10 degrees and 27 degrees, respectively). The surface potential on the smooth coating, assessed using Kelvin force microscopy, showed a sharp distribution, but that on the rough coating ranged widely, implying large chemical heterogeneity including residual SiOH groups. The freezing temperature of a supercooled water droplet on the rough coating was higher than that on the smooth coating.

DOI： 10.1021/la701077p

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Language：English   Publisher：SPRINGER  

Mixing bioactive ceramic powders with polymers is an effective method for generating bioactivity to the polymer-matrix composites but it is necessary to incorporate up to 40 vol% of bioactive ceramic powder. However, such a high mixing ratio offsets the advantages of the flexibility and formability of polymer matrix and it would be highly advantageous to lower the mixing ratio. Since surface loading of ceramic powders in the polymer is thought to be an effective way of reducing the mixing ratio of the ceramic powder while maintaining bioactive activity, CaSiO3/poly-lactic acid (PLA) composites were prepared by three methods; (1) casting, (2) spin coating and (3) hot pressing. In methods (1) and (2), a suspension was prepared by dissolving PLA in chloroform and dispersing CaSiO3 powder in it. The suspension was cast and dried to form a film in the case of method (1) while it was spincoated on a PLA substrate in method (2). In method (3), CaSiO3 powder was surface loaded on to a PLA substrate by hot-pressing. The bioactivity of these samples was investigated in vitro using simulated body fluid (SBF). Apatite formation was not observed in the samples prepared by method (1) but some apatite formation was achieved by mixing polyethylene glycol (PEG) with the PLA, producing a porous polymer matrix. In method (2), apatite was clearly observed after soaking for 7 days. Enhanced apatite formation was observed in method (3), the thickness of the resulting apatite layers becoming about 20 mu m after soaking for 14 days. Since the amount of CaSiO3 powder used in these samples was only <= 0.4 vol%, it is concluded that this preparation method is very effective in generating bioactivity in polymer-matrix composites by loading with only very small amounts of ceramic powder.

DOI： 10.1007/s10856-007-3059-9

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Language：English  

For this study, we evaluated photoinduced surface roughness variation of polycrystalline anatase thin films under different atmospheres using atomic force microscopy (AFM). A TiO2 thin film with large grains was prepared using the sol-gel process and vacuum ultraviolet (VUV) irradiation before firing. Upon UV illumination, the surface image became blurred with an apparent surface roughness increase in ambient air. The appearance of this image change was delayed in dry air, and was not observed in dry nitrogen. These results imply that this photoinduced surface change is related to water adsorption from the atmosphere. © 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jphotochem.2007.03.013

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Language：English   Publisher：ELSEVIER SCIENCE SA  

For this study, we evaluated photoinduced surface roughness variation of polycrystalline anatase thin films under different atmospheres using atomic force microscopy (AFM). A TiO2 thin film with large grains was prepared using the sol-gel process and vacuum ultraviolet (VUV) irradiation before firing. Upon UV illumination, the surface image became blurred with an apparent surface roughness increase in ambient air. The appearance of this image change was delayed in dry air, and was not observed in dry nitrogen. These results imply that this photoinduced surface change is related to water adsorption from the atmosphere. (c) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jphotochem.2007.03.013

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Language：English   Publisher：ELSEVIER SCIENCE BV  

We investigated the processing of a metal nanogranular thin film of Co-Ti-O system by combining a colloidal wet process (inverse micelle method) and a dry process (plasma treatment). Both TEM and EDS analyses revealed,that the film was prepared along with suppression of metal cobalt nanoparticles' oxidization. Results showed that plasma processing provides new possibilities for processing of materials that are difficult to prepare under equilibrium conditions. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matlet.2006.08.044

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Language：English   Publisher：ELSEVIER SCIENCE BV  

We investigated the processing of a metal nanogranular thin film of Co-Ti-O system by combining a colloidal wet process (inverse micelle method) and a dry process (plasma treatment). Both TEM and EDS analyses revealed,that the film was prepared along with suppression of metal cobalt nanoparticles' oxidization. Results showed that plasma processing provides new possibilities for processing of materials that are difficult to prepare under equilibrium conditions. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matlet.2006.08.044

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Mixing bioactive ceramic powders with polymers is an effective method for generating bioactivity to the polymer-matrix composites but it is necessary to incorporate up to 40 vol% of bioactive ceramic powder. However, such a high mixing ratio offsets the advantages of the flexibility and formability of polymer matrix and it would be highly advantageous to lower the mixing ratio. Since surface loading of ceramic powders in the polymer is thought to be an effective way of reducing the mixing ratio of the ceramic powder while maintaining bioactive activity, CaSiO3/poly-lactic acid (PLA) composites were prepared by three methods; (1) casting, (2) spin coating and (3) hot pressing. In methods (1) and (2), a suspension was prepared by dissolving PLA in chloroform and dispersing CaSiO3 powder in it. The suspension was cast and dried to form a film in the case of method (1) while it was spin-coated on a PLA substrate in method (2). In method (3), CaSiO3 powder was surface loaded on to a PLA substrate by hot pressing. The bioactivity of these samples was investigated in vitro using simulated body fluid (SBF). Apatite formation was not observed in the samples prepared by method (1) but some apatite formation was achieved by mixing polyethylene glycol (PEG) with the PLA, producing a porous polymer matrix. In method (2), apatite was clearly observed after soaking for 7 days. Enhanced apatite formation was observed in method (3), the thickness of the resulting apatite layers becoming about 20 mu m after soaking for 14 days. Since the amount of CaSiO3 powder used in these samples was only <= 0.4 vol%, it is concluded that this preparation method is very effective in generating bioactivity in polymer-matrix composites by loading with only very small amounts of ceramic powder.

DOI： 10.1007/s10856-006-0094-x

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Language：English   Publisher：AMER INST PHYSICS  

An analysis system was developed to evaluate the sliding behavior of a liquid droplet on a hydrophobic surface. This system enables continuous and simultaneous measurement of both the sliding acceleration and shape deformation during the sliding of a liquid droplet. Moreover, the velocity vector of the internal fluidity of a sliding droplet was obtained by employing particle image velocimetry in the analysis system. This evaluation method pioneers the measurement of the dynamic wettability of a hydrophobic solid surface.

DOI： 10.1063/1.2716005

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Al-containing CaO-SiO2-H2O phases were prepared by hydrothermal treatment of mixtures of paper sludge ash (PSA) with various silica and calcia sources and their properties were determined with particular reference to the simultaneous uptake of ammonium and phosphate ions, which are implicated in the eutrophication of lakes and ponds. After examination of various silica and calcia sources, Ca(OH)(2) and SiO2 Sol were selected as the most appropriate starting materials. Dry milling was found to be superior to wet milling in avoiding contamination from the milling media during mixing. Nine samples with three different Ca/Si ratios and Al2O3 contents were prepared with various mass ratios of Ca(OH)(2), PSA and SiO2. The chemical compositions of the hydrothermal products of these mixtures moved towards the tieline of CaSiO3-PSA, with respect to the starting compositions. The major phase formed in all samples was poorly crystalline C-S-H(I), with hydroxysodalite also formed in the Al-containing mixtures. All the products showed a capacity for the simultaneous uptake of ammonium and phosphate ions. The saturated sorption capacities calculated from the Langmuir equation ranged from 0.9 to 2.4 mmol/g for the ammonium ion and from 3.3 to 5.2 mmol/g for the phosphate ion. Since the sorption capacities for both ions increased with increasing Ca contents of the product, substitution of Ca2+ for NH4+ and the formation of calcium phosphate phases such as apatite and brushite by precipitation are thought to be the main sorption mechanisms. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2006.07.017

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Effects of TiO2 powder addition on sonochemical destruction of 1,4-dioxane in water were investigated through comparison of a SiO2 powder that had similar specific surface area. Results show that addition of TiO2 is more effective for decomposition of 1,4-dioxane in water than addition of SiO2. The contribution of photocatalytic destruction through sonoluminescence is not a dominant mechanism for acceleration of sonochemical reactions by adding TiO2. Sonication of TiO2-added water generated thermally excited holes in this case. Moreover, intrinsic oxygen vacancies in TiO2 surface play an important role in achieving high decomposition efficiency by producing cavitation. The addition of reduced TiO2 powder increases both the ultrasonication energy that is consumed in water and the destruction efficiency of 1,.4-dioxane. (C) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ultsonch.2006.06.001

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Effects of TiO2 powder addition on sonochemical destruction of 1,4-dioxane in water were investigated through comparison of a SiO2 powder that had similar specific surface area. Results show that addition of TiO2 is more effective for decomposition of 1,4-dioxane in water than addition of SiO2. The contribution of photocatalytic destruction through sonoluminescence is not a dominant mechanism for acceleration of sonochemical reactions by adding TiO2. Sonication of TiO2-added water generated thermally excited holes in this case. Moreover, intrinsic oxygen vacancies in TiO2 surface play an important role in achieving high decomposition efficiency by producing cavitation. The addition of reduced TiO2 powder increases both the ultrasonication energy that is consumed in water and the destruction efficiency of 1,.4-dioxane. (C) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ultsonch.2006.06.001

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A hydrophobic to hydrophilic gradient surface was prepared using the tuned photodegradation of an alkylsilane self-assembled monolayer (SAM) using irradiation of vacuum ultraviolet light (wavelength = 172 nm). The water contact angle on the photodegraded SAM surface was adjusted using the intensity and time photoirradiation parameters. The formation of a gradient was confirmed by fluorescent labeling. The water drop moved from the hydrophobic to hydrophilic surface with a velocity that depended on the gradient. The higher the gradient, the faster the water moved. For the first time, we have prepared a gradient surface using photodegradation where the movement of a water drop was regulated by the degree of gradation. Considering that the photodegradation technique can be applied to various surfaces and to lithography, this technique will be useful for various material surfaces.

DOI： 10.1021/la0624992

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Motion and deformation of a water-based magnetic fluid on a hydrophobic surface were investigated under gravity and a magnetic field. Surface energy and the resultant contact angle of the magnetic fluid depend on the surfactant concentration. The fluid viscosity is governed mainly by magnetite concentration. The front edge of the droplet moved under a weak external field. The rear edge required a higher external field for movement. The forces of gravity and the magnetic field for moving of the front edge are almost equal. However, those of the rear edge are different. The motion of magnetic fluids by an external field depends on concentrations of surfactants and magnetic particles, the external field, and experimental assembly. © 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apsusc.2006.06.062

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Simultaneous uptake of Ni2+, NH4+, and PO43- by amorphous CaO-Al2O3-SiO2 (C-A-S) compounds was investigated using batch and column methods. Fifteen different C-A-S samples with systematically varied chemical compositions were prepared by coprecipitation from ethanol-water solutions containing Ca(NO3)(2)(.)4H(2)O, Al(NO3)(3)(.)9H(2)O, and Si(OC2H5)(4), using NH4OH as the precipitating agent. The resulting precipitates were dried and heated at various temperatures to produce the C-A-S samples, which were then characterized by XRD, FTIR, solid state MAS NMR, DTA-TG, and N-2 adsorption. All the C-A-S samples prepared at 600-900 degrees C were amorphous, apart from the CaO-rich samples. Simultaneous uptake of Ni2+, NH4+, and PO43- was determined by a batch method using a solution with an initial concentration of 2 mM. In these experiments, the uptake abilities of the C-A-S samples for Ni2+ and PO43- were high, but were relatively low for NH+. The uptake abilities for Ni2+ and PO43- increased but that for NH+ decreased as the silica content in the C-A-S decreased, suggesting that similar uptake mechanisms (ion substitution and/or precipitation) are operating for Ni2+ and PO43- but the uptake mechanism for NH4+ is different (physical adsorption). The column experiments indicate that the order of uptake ability of C-A-S for the three ions is Ni-4(+) << PO43- < Ni2+. Although the silica content of the C-A-S does not have the expected influence on the uptake of these three ions, for NH4+ it plays an important role in the formation of the amorphous phase and also in the suppression of Ca2+ and/or Al3+ release from the C-A-S during the uptake experiments. The optimum uptake properties of the C-A-S can thus be controlled by adjusting the chemical compositions and heating conditions under which the samples are prepared. (c) 2006 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2006.10.007

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Simultaneous uptake of Ni2+, NH4+, and PO43- by amorphous CaO-Al2O3-SiO2 (C-A-S) compounds was investigated using batch and column methods. Fifteen different C-A-S samples with systematically varied chemical compositions were prepared by coprecipitation from ethanol-water solutions containing Ca(NO3)(2)(.)4H(2)O, Al(NO3)(3)(.)9H(2)O, and Si(OC2H5)(4), using NH4OH as the precipitating agent. The resulting precipitates were dried and heated at various temperatures to produce the C-A-S samples, which were then characterized by XRD, FTIR, solid state MAS NMR, DTA-TG, and N-2 adsorption. All the C-A-S samples prepared at 600-900 degrees C were amorphous, apart from the CaO-rich samples. Simultaneous uptake of Ni2+, NH4+, and PO43- was determined by a batch method using a solution with an initial concentration of 2 mM. In these experiments, the uptake abilities of the C-A-S samples for Ni2+ and PO43- were high, but were relatively low for NH+. The uptake abilities for Ni2+ and PO43- increased but that for NH+ decreased as the silica content in the C-A-S decreased, suggesting that similar uptake mechanisms (ion substitution and/or precipitation) are operating for Ni2+ and PO43- but the uptake mechanism for NH4+ is different (physical adsorption). The column experiments indicate that the order of uptake ability of C-A-S for the three ions is Ni-4(+) << PO43- < Ni2+. Although the silica content of the C-A-S does not have the expected influence on the uptake of these three ions, for NH4+ it plays an important role in the formation of the amorphous phase and also in the suppression of Ca2+ and/or Al3+ release from the C-A-S during the uptake experiments. The optimum uptake properties of the C-A-S can thus be controlled by adjusting the chemical compositions and heating conditions under which the samples are prepared. (c) 2006 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2006.10.007

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Motion and deformation of a water-based magnetic fluid on a hydrophobic surface were investigated under gravity and a magnetic field. Surface energy and the resultant contact angle of the magnetic fluid depend on the surfactant concentration. The fluid viscosity is governed mainly by magnetite concentration. The front edge of the droplet moved under a weak external field. The rear edge required a higher external field for movement. The forces of gravity and the magnetic field for moving of the front edge are almost equal. However, those of the rear edge are different. The motion of magnetic fluids by an external field depends on concentrations of surfactants and magnetic particles, the external field, and experimental assembly. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apsusc.2006.06.062

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DOI： 10.1007/s10856-007-3059-9

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DOI： 10.4028/0-87849-454-5.281

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DOI： 10.5182/jaie.18.270

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DOI： 10.1246/cl.2007.1020

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DOI： 10.1016/j.materresbull.2006.12.011

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DOI： 10.5182/jaie.18.270

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DOI： 10.1016/j.materresbull.2006.12.011

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Porous alumina ceramics having unidirectionally aligned cylindrical pores were prepared by extrusion method and compared with porous ceramics having randomly distributed pores prepared by conventional method, and their gas permeability and mechanical properties were investigated. SEM micrographs of the porous alumina ceramics prepared by the extrusion method using nylon fibers as the pore former showed excellent orientation of cylindrical pores. The bending strength and Weibull modulus of the extruded porous alumina ceramics with 39% porosity were 156 MPa and 17, respectively. These mechanical properties of extruded samples were higher than those of the conventional porous alumina ceramics. The strength decreased from 156 to 106 MPa with increasing pore size from 8.5 to 38 mu m. The gas permeability of the extrusion samples is higher than that of the conventional samples and increased with increasing of porosity and pore size. (c) 2006 Published by Elsevier Ltd.

DOI： 10.1016/j.jeurceramsoc.2006.02.030

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DOI： 10.1016/j.jcis.2007.05.036

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DOI： 10.1246/cl.2007.1020

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DOI： 10.4028/0-87849-454-5.281

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DOI： 10.5182/jaie.18.270

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DOI： 10.1016/j.jhazmat.2006.07.017

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DOI： 10.1246/cl.2007.1020

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DOI： 10.5182/jaie.18.270

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DOI： 10.4028/0-87849-454-5.281

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Glass-ceramics were prepared from sludge generated in a water purification process. The main constituents of this sludge were Si0(2) and Al2O3, with considerable amounts of Fe2O3 and MnO also present. The batch composition of the parent glass was adjusted to be close to the composition of the eutectic point in the CaO-Al2O3-SiO2 System by mixing the sludge with CaCO3 and waste soda-lime glass. The samples were melted at 1300 degrees C for 2 h and quenched in water. The resulting glass cullet was ground to < 100 mesh in a ball mill, uniaxially pressed to form green bodies and fired at 700-1250 degrees C to densify and crystallize. Crystallization occurred at > 850 degrees C, forming gehlenite (Ca2Al2SiO7) and wollastonite (CaSiO3) above 900-950 degrees C. The color of the sample changed from black to yellow-brown upon crystallization. The average four-point bending strength and Vickers microhardness of the glass-ceramics heated at 1000 degrees C (99 MPa and 5.2 GPa) was comparable with the values of commercial glass-ceramics. The chemical durability in acid and alkali solutions was 17.7 and 0.23 mg/cm(2), respectively, showing excellent durability in alkali solution. (c) 2006 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

DOI： 10.1016/j.ceramint.2005.11.009

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DOI： 10.1016/j.jcis.2007.05.036

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Porous alumina ceramics having unidirectionally aligned cylindrical pores were prepared by extrusion method and compared with porous ceramics having randomly distributed pores prepared by conventional method, and their gas permeability and mechanical properties were investigated. SEM micrographs of the porous alumina ceramics prepared by the extrusion method using nylon fibers as the pore former showed excellent orientation of cylindrical pores. The bending strength and Weibull modulus of the extruded porous alumina ceramics with 39% porosity were 156 MPa and 17, respectively. These mechanical properties of extruded samples were higher than those of the conventional porous alumina ceramics. The strength decreased from 156 to 106 MPa with increasing pore size from 8.5 to 38 mu m. The gas permeability of the extrusion samples is higher than that of the conventional samples and increased with increasing of porosity and pore size. (c) 2006 Published by Elsevier Ltd.

DOI： 10.1016/j.jeurceramsoc.2006.02.030

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Porous alumina ceramics with uni-directionally aligned pores were prepared by an extrusion method using 0-40 vol.% poly (vinyl acetate) (PVAC) as the pore former. A paste was prepared by mixing 25 mass% distilled water, 4 mass% methylcelullose, 8 mass% oleic acid and 0.8 mass% ammonium poly (carboxylic acid). This paste was molded into a 10 mm 0 body using a ram-type extruder, dried at room temperature for 24 h, calcined at 600 degrees C for 1 h and sintered at 1500 degrees C for 2 h in air. The PVAC added to the paste was homogeneously dispersed and formed particles 0.1-150 mu m in size which extended in the extrusion direction and were converted to through-hole pores after sintering. The resulting pore size distribution in the samples was bimodal, centered at about 0.4 mu m with a broad peak at about 70 mu m dia. The resulting porous alumina ceramics showed high gas permeability because of their uni-directionally oriented through-hole pore structure. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jeurceramsoc.2006.05.079

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The current study investigated the effects of vacuum ultraviolet (VUV) illumination and seeding on the crystallization of sol-gel-derived titanium dioxide (TiO2) precursor films on Si(100) and Pyrex glass substrates by plasma treatment. To improve the film microstructure to one that is amenable to crystallization, VUV illumination is found to be effective. However, crystallization behavior suggests that a proper balance between decomposition of organic compounds and densification by dehydration is important for the treatment. The combination of seeding and VUV illumination is effective even for crystallization by plasma treatment on both Si(100) and Pyrex glass substrates. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.surfcoat.2006.06.014

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In the current work, we prepared a TiO2 coating on stainless mesh using electrophoretic deposition (EPD), and applied voltage to a stainless mesh to examine the synergy effect on photocatalysis of both 1,4-dioxane and ethylene glycol diformate (EGDF), a main intermediate of the photocatalysis of 1,4-dioxane. The photocatalytic decomposition rate of 1,4-dioxane depends on applying voltage under diffusion-limited reaction conditions. Ethylene glycol diformate and 1,4-dioxane exhibited inverse voltage dependence. Voltage swing provides high-efficiency photocatalysis of 1,4-dioxane while suppressing EGDF formation. This method will be effective for a photocatalysis system containing several chemicals, each with different voltage dependence. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.catcom.2006.05.016

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Language：English   Publisher：ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD  

Uptake properties of Ni2+ were examined for unmilled and milled paper sludge calcined at various temperatures to develop a new usage of waste paper sludge. Since paper sludge mainly consists of cellulose ([C6H10O5](n)) fibers, calcite (CaCO3) kaolinite (Al2Si2O5(OH)(4)) and talc (Mg3Si4O10(OH)(2)), amorphous and crystalline CaO(MgO)-Al2O3-SiO2 compounds are formed by calcining paper sludge. Wet and dry milling treatments were performed to accelerate solid-state reaction to form the above mentioned target compounds. The crystalline phases originally present decompose at increasing calcining temperature (up to 800 degrees C) in the order cellulose < kaolinite < calcite < talc. An amorphous phase was formed in the samples below 800 degrees C and the temperatures changed depending on the milling conditions in the order dry milled < wet milled < unmilled. Gehlenite (Ca2Al2SiO7) and anorthite (CaAl2Si2O8) crystallized by calcining at 900 degrees C in all the samples, formed by solid-state reaction of kaolinite with calcite. The Si-29 and Al-27 MAS NMR spectra of the amorphous samples were similar to those of crystalline phases, suggesting that the local structure of the amorphous phase resembles the crystalline structures. Maximum Ni2+ uptake occurred in the dry-milled samples calcined at 600 degrees C, and wet-milled and unmilled samples calcined at 700 degrees C, respectively. The dry-milled and calcined at 600 degrees C sample showed the highest Ni2+ uptake (4.54 mmol/g) and an uptake rate of 3.5 mu mol/(g min). (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jenvman.2005.09.014

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Porous materials consisting of activated carbon and amorphous CaO-Al2O3-SiO2 (CAS) compound were prepared from refuse paper and plastic fuel (RPF), (a mixture of old paper and plastic) by carbonizing and/or activating treatments. Samples formed by chemical activation using K2CO3 showed a high specific surface area (S-BET) of 1330 m(2)/g but a lower ash content due to being washed after activation. By contrast, samples prepared by physical activation using steam showed rather lower SBET (510 m(2)/g) due to higher ash contents. The physically activated samples showed much higher uptake properties for Ni2+ (a representative heavy metal) and phosphate ions (a representative of a harmful oxyanion) than the chemically activated samples because of the higher content of amorphous CAS in the former samples. By contrast, the chemically activated samples showed higher uptake for methylene blue (MB, a representative organic material) than the physically activated samples because of the higher activated carbon content of higher surface area. Although differences in the sorption properties for Ni2+, phosphate ion and MB were found between the physically and chemically activated samples, both samples show excellent multiple sorption properties for cation-anion combinations and inorganic-organic sorbents. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2006.02.008

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Faujasite-type zeolite films were prepared on foamed stainless steel by the in-situ crystallization method. Precursor solutions were prepared by dissolving water glass and NaAlO2 in a NaOH solution and aged at room temperature for two days. The concentrations of the starting materials were varied from 0.29 to 2.3 M( in SiO2 concentration) keeping the molar ratios of Na2O: SiO2: Al2O3 fixed at 3.6: 3.0: 1.0. The foamed stainless steel substrate had about 90% of porosity and an average pore size of 600 mu m. It was dip-coated in the precursor solution four times, then hydrothermally treated at 80 degrees, 110 degrees and 150 degrees C for 6 - 48 h. The XRD patterns and SEM photographs revealed that faujasite-type zeolite was formed predominantly at a SiO2 concentration of 1.1 M, temperature of 110 degrees C and duration of 24 h, with a product particle size of 2 - 5 mu m. At higher concentrations of the precursor solution, hydroxylsodalite becomes the major product rather than faujasite-type zeolite. The adherence strength of the zeolite grains deposited on the foamed stainless steel is higher in the in-situ crystallization method than when a conventional solution method is used. Thus, the in-situ crystallization method is concluded to be effective for preparing zeolite films even on metal substrates.

DOI： 10.1007/s10832-006-9931-z

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This study measured sliding acceleration of water droplets on hydrophobic solid surfaces and used expanding and contracting method to compare that value with dynamic contact angles. Sliding action of the droplet was classified into three motion categories: constant accelerated motion, constant velocity and stasis. Differences exist in the dependencies of contact radius and the injection-suction rate in dynamic contact angle hysteresis according to these categories. This method is an effective indicator of water droplets' sliding acceleration. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.susc.2006.06.039

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Static and dynamic hydrophobicities of water droplet on a patterned surface prepared using fluoroalkylsilanes with different molecular chain lengths were investigated. Contact angles on the patterned surfaces well agreed with values predicted using Cassie's theory. On the same line width ratio, total retention force was governed by the fluoroalkylsilane with slow-sliding acceleration. The total retention force decreased with the decreasing width ratio of silane with slow-sliding acceleration on the surface. These results imply that the sliding acceleration of water droplets on a hydrophobic surface depends both on chemical composition and patterning structure. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.susc.2006.04.044

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Mg-Al-CO3 type layered double hydroxides (LDHs) with Mg/Al ratios ranging from 2 to 5 were synthesized by coprecipitation. Composites with sodium oleate/LDH were prepared by ion exchange and reconstruction of the LDH in sodium oleate solution. The amount of sodium oleate in the composites prepared by this reconstruction method was higher than that in samples prepared by the ion-exchange method. The basal spacings of the LDHs increased to 3.9 and 1.8 nm after synthesis of the composites, these spacings being in good agreement with models based on the assumption that the oleate ions are intercalated as bilayer and/or micelle structures, and as monolayers in the LDH interlayers, respectively. The number of sorbed oleate ions was higher than calculated from the anion-exchange capacities of the LDHs in most of the samples, increasing as the Mg/Al ratios of the LDHs were increased from 2 to 5. These results suggest that the oleate ions are present not only in the interlayers but also on the surfaces of the LDH particles. The acid-resistant properties of the composites were found to be much higher than for the pure LDHs. It is thus confirmed that the surfaces of the LDH particles in the composites are mostly covered with sorbed oleate ions and that the composites are good candidates as drug delivery materials. (c) 2006 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2006.01.033

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Photoinduced microstructural changes in transparent anatase thin films with large-grain polycrystallites (-200 nm) were evaluated using atomic force microscopy (AFM). Films were subjected to a vacuum ultraviolet (VUV) pretreatment before heating at 500 °C. Photoinduced wettability of the films was subsequently confirmed. Upon UV illumination, the surface image became blurred with an apparent increased surface roughness. The image sharpened gradually as the surface returned to its initial state. This microstructural surface change is most pronounced at grain boundaries. © 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jphotochem.2005.09.023

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Photoinduced microstructural changes in transparent anatase thin films with large-grain polycrystallites (-200 nm) were evaluated using atomic force microscopy (AFM). Films were subjected to a vacuum ultraviolet (VUV) pretreatment before heating at 500 degrees C. Photoinduced wettability of the films was subsequently confirmed. Upon UV illumination, the surface image became blurred with an apparent increased surface roughness. The image sharpened gradually as the surface returned to its initial state. This microstructural surface change is most pronounced at grain boundaries. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jphotochem.2005.09.023

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Both fluoroalkylsilane (FAS) and octadecyltrimethoxysilane (ODS) were coated on oxidized silicon wafers using soaking and CVD method. Smooth coatings with Ra values of less than 1 nm were attained. The slope of the sliding acceleration against the inverse of the droplet mass showed an inflection point. That point shifted to the direction of smaller droplets with decreasing FAS ratio to ODS. The water droplets' length was increased when the sliding velocity was increased. Fluoroalkylsilane addition to ODS increases the interaction between water and the hydrophobic surface. Results showed that the sliding acceleration of a water droplet depends strongly on the surface ratio of these silanes. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.susc.2006.03.015

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In the current study, we used a high-speed camera system with particle image velocimetry to observe the internal fluidity of water droplets during sliding. The droplets' velocity during sliding was controlled by slipping and rolling motions. On the superhydrophobic surface, with a contact angle of 150, the droplet fell at high velocity by slipping. However, on a normal hydrophobic surface whose water contact angle was around 100, both slipping and rolling controlled the droplet's velocity during sliding. In addition, the advancing velocity might be large when the slip velocity is large and the contact area is small.

DOI： 10.1021/la060323u

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Photoinduced microstructural changes in transparent anatase thin films with large-grain polycrystallites (-200 nm) were evaluated using atomic force microscopy (AFM). Films were subjected to a vacuum ultraviolet (VUV) pretreatment before heating at 500 degrees C. Photoinduced wettability of the films was subsequently confirmed. Upon UV illumination, the surface image became blurred with an apparent increased surface roughness. The image sharpened gradually as the surface returned to its initial state. This microstructural surface change is most pronounced at grain boundaries. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jphotochem.2005.09.023

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Al-containing mesoporous silicas were synthesized by hydrothermal treatment of microporous silica prepared by selectively acid leached metakaolinites with Si/Al = 3.9-92.5 mixed with a surfactant of cetyltrimethylammonium bromide (CTABr). The Specific surface area of the products increased with higher surfactant/microporous silica (surf/Si) ratio and Si/Al ratio of the microporous silica. reaching about 1400 m(2)/g at CTABr/Si >= 0.1 and Si/Al >= 40. The XRD patterns of these products show a hexagonal (100) peak with the lattice parameter a(0) = 4.2-4.3 nm and the N-2 adsorption isotherms show steep increase of adsorption between relative pressure of 0.3 and 0.4. Hexagonal mesoporous microstructure is observed by high resolution TEM. The pore size distributions of the products Show a sharp peak at 2.8 nm by the BJH method. The high specific surface area of the present mesoporous samples is attributed to the lower matrix density and Surface roughness of mesopore wall. The highest specific surface area of the products reached LIP to 1420 m(2)/g and this value is apparently higher than those reported in hexagonal mesoporous silicas. A unique microporous structure of the starting material is thought to be related to achieve such a high specific surface area of the products. (c) 2005 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2005.10.051

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Language：English   Publisher：ELSEVIER SCIENCE SA  

The crystallization of amorphous metal oxide thin films was achieved by RF plasma treatment. Although various amorphous films are crystallized after 2 min or so, the sample temperature is lower than 150 degrees C without compulsory cooling even when the films are treated for I It. The oxygen gas pressure on the plasma treatment was found to be the key parameter on the crystallization. This treatment works on amorphous films of various materials, independently of the film preparation method and substrate materials. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.tsf.2005.07.244

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Various 2: 1 type clay minerals were activated by H2SO4 treatment and their solid acidities were evaluated by NH3-temperature programmed desorption (TPD). Clay minerals with various degrees of Al substitution in the tetrahedral sheets were used as the starting materials. These included montmorillonite (ideally no tetrahedral Al), saponite (low content of tetrahedral Al), vermiculite (intermediate content of tetrahedral Al) and phlogopite (high tetrahedral Al content). All these samples showed increased solid acidity after selective leaching, the solid acidities varying in the order phlogopite < montmorillonite < vermiculite < saponite. The NE3-TPD spectra were deconvoluted into two peaks; the L-peak at < 200 degrees C corresponds to a weak acid site and the H-peak at > 250 degrees C corresponds to a strong acid site. The temperature of the H-peak was lowest in phlogopite (252 degrees C) and highest in saponite (305 degrees C). The generation of solid acidity in these samples is found to be related to the evolution of new tetrahedral Al sites showing a slightly different Al-27 MAS NMR chemical shift from the original tetrahedral Al NMR resonance. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.clay.2005.10.014

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Language：English   Publisher：ELSEVIER SCIENCE SA  

TiO2-hydroxyapatite (HAp) hybrid films were prepared by laminating TiO2 films with holes on the HAp film. We prepared transparent porous HAp film through spray pyrolysis deposition (SPD) method. The HAp possessed affinity against proteins. TiO2 films were prepared using phase separation of alkoxide. The holes provided from this process serve as an adsorption field and photocatalytic reaction field for reactants. This work demonstrated that the TiO2-HAp hybrid films produced by this process are candidates for photocatalytic decomposition of germs, viruses, and other biohazardous substances in the environment. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jphotochem.2005.05.019

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Language：English   Publisher：AMER CHEMICAL SOC  

Flat films of methyl methacrylate-fluoroalkyl methacrylate copolymers were prepared, and their hydrophobicity was investigated. It Was revealed that the F concentration directly affects the static hydrophobicity on the flat polymer surface in a systematic manner. Furthermore, the sliding behavior of a water droplet on these surfaces depends on the static hydrophobicity; the sliding motion changes from constant velocity to constant acceleration with an increase in the water contact angle.

DOI： 10.1021/ja050617m

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Language：English   Publisher：ELSEVIER SCI LTD  

Glass-ceramics were prepared from mixtures of wastes generated from refining of silica sand and kaolin clay (Kira) and paper sludge ash. Kira and paper sludge ash were mixed in mass ratios of 55/45. The mixtures were melted at 1400 degrees C and quenched in water to obtain glasses. The quenched glasses were ground to < 48 mesh and used to prepare glass-ceramics. Crystallization of the parent glass occurred above 950 degrees C, producing quartz solid solution at 1000 degrees C and cristobalite at 1100 degrees C as the major crystalline phases. The color of the glass-ceramics is white or slightly pale yellow. The four-point bending strengths of the as-fired glass-ceramics range from 63 to 66 MPa and the Vickers microhardness values from 6.0 to 6.4 GPa. The average linear thermal expansion coefficients of the glass-ceramics range from 6.3 x 10(-6) /degrees C to 8.1 x 10(-6) /degrees C (30-380 degrees C) and show non-linearity around the phase transition temperatures of quartz and cristobalite. The chemical durability of the resulting glass-ceramics is excellent in alkali but poor in acid solution. The glass-ceramics show rather better performance than commercial glass-ceramics even when prepared solely from wastes starting materials. (c) 2005 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

DOI： 10.1016/j.ceramint.2005.06.008

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Language：English   Publisher：ELSEVIER SCI LTD  

Porous alumina ceramics with unidirectionally-oriented pores were prepared by extrusion. Carbon fibers of 14 mu m diameter and 600 mu m length to be used as the pore-forming agent were kneaded with alumina, binder and dispersing agent. The resulting paste was extruded, dried at 100 degrees C, degreased at 1000 degrees C and fired at 1600 degrees C for 2 h. SEM showed a microstructure of dispersed highly oriented pores in a dense alumina matrix. The pore area in the cross section was 25.3% with about 1700 pores/mm(2). The pore size distribution of the fired body measured by Hg porosimetry showed a sharp peak corresponding to the diameter of the burnt-out carbon fibers. The resulting porous alumina ceramics with 38% total porosity showed a fracture strength of 171 MPa and a Young's modulus of 132 GPa. This strength is significantly higher than the reported value for other porous alumina ceramics even though the present pore size is much larger. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jeurceramsoc.2004.11.015

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Language：English   Publisher：TAYLOR & FRANCIS INC  

This study concerns with the utilization of waste paper sludge, which contains mainly cellulose fibers and inorganic fillers together with coating materials such as calcite, kaolinite and talc. Paper sludge was fired at 500-900 degrees C for 6 h. The crystalline phases originally present decomposed at increasing temperatures (up to 800 degrees C) in the order kaolinite < calcite < talc. Gehlenite was formed at 800 degrees C in increasing amounts above this temperature together with small amounts of magnesium aluminum silicate and anorthite. The uptake of these fired samples of Ni2+, PO43- and NH4+ was investigated at room temperature. Paper sludge fired at 700 degrees C showed the highest uptake of Ni2+, PO43- and NH4+ (3.93, 1.28 and 0.49 mmol/g, respectively). The main process responsible for the sorption of these ions is the ion change along with precipitation with higher solution pH. From an economic point of view, paper sludge is the cheapest raw material for preparing adsorbents with high uptake ability for heavy metal, phosphate and ammonium ions.

DOI： 10.1080/10934520600575101

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Language：English   Publisher：ELSEVIER SCIENCE BV  

In the current work, we prepared TiO2 thin films using vacuum ultraviolet (VUV) irradiation of several different intensities before firing. We then investigated effects of VUV intensity and alkoxide mixtures on the microstructural evolution of the films. The microstructure of the film without VU-V treatment comprises uniform anatase grains. Grains in films with VUV irradiation gradually form a domain-like microstructure with increasing VUV intensity. The heterogeneous hydrolysis rate in the mixed alkoxide will trigger formation of the domain-like microstructure. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.susc.2005.09.016

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Language：English   Publisher：ELSEVIER SCIENCE BV  

The present study demonstrates that H2SO4 treatment of TiO2 surface provides higher photocatalytic decomposition efficiency on gaseous toluene under a proper condition. Deactivation was less remarkable for H2SO4-treated TiO2 than for pure TiO2 with repeated toluene injections. This result is attributable to the assist of the decomposition of intermediates by surface strong acid itself or resultant high quantum yield by decreasing recombination possibility between electrons and holes on the powder surface. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.catcom.2005.07.006

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Language：English   Publisher：SPRINGER  

Composites of carbon/zeolite with corrugated structures were prepared by carbonization, steam activation and/or hydrothermal treatment of corrugated paper. No zeolite formation resulted from conventional hydrothermal treatment of the carbonized and activated samples in NaOH solution but zeolite Na P1 was formed by addition of silica to the solution. By contrast, zeolites Na P1 and Na A were formed by the in-situ crystallization method (hydrothermal treatment of solid samples impregnated with NaOH solution). With higher impregnating NaOH concentrations, longer reaction times and higher reaction temperatures, the products changed to sodalite- and cancrinite-type compounds. Hydrothermal treatment was effective in increasing the specific surface area of the products by the formation of zeolite from amorphous calcium aluminosilicate, and also increased the mechanical strength by gluing together the carbon fibers in the samples. The resulting samples showed enhanced adsorption for polar molecules such as ammonia, water vapor and methanol due to the formation of composites of activated carbon with hydrophilic zeolites.

DOI： 10.1007/s10934-005-3126-x

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Porous silica was prepared by selective leaching of chlorite and the influence on the porous properties of the product of the acid type and acid concentration, solution temperature and leaching time were investigated. After leaching, only SiO2 remained, the other components being selectively leached from the sample in the order MgO < Fe2O3< Al2O3. The specific surface area of the product obtained by H2SO4-leaching was greater than with HNO3- and HCl-leaching. The highest specific surface area (394 m(2)/g) was obtained by leaching the chlorite with 5 N H2SO4 at 90 degrees C for 1.5 It. The pore size distribution of the products showed a maximum at about 5 nm with a pore size much larger than would be expected for selective leaching of the octahedral chlorite sheets. The Si-29 MAS NMR spectra of the products showed a stronger Q(4) peak (related to a framework structure unit) than the Q(3) peak (from a layer structure unit), suggesting the presence of a framework structure similar to silica gel rather than the original layered structure. The resultant structure of the silica product results in a lower specific surface area than found in leached vermiculite and phlogopite. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.clay.2005.04.001

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Language：English   Publisher：ELSEVIER SCIENCE BV  

A series of nCaO center dot Al(2)O(3)center dot 2SiO(2) samples (n = 1-4) were prepared by solid-state reaction of mechanochemically treated mixtures of kaolinite and calcite fired at 600-1000 degrees C for 24 h. All the samples were X-ray amorphous after firing at 600-800 degrees C but had crystallized by 900 degrees C. The main crystalline phases were anorthite (n = 1), gehlenite (n = 2 and 3) and larnite (n = 4). The uptake of Ni2+ by nCaO center dot Al(2)O(3)center dot 2SiO(2) samples fired at 800 and 900 degrees C was investigated at room temperature using solutions with initial Ni2+ concentrations of 0.1-50 mmol/l. Amorphous samples (fired at 800 degrees C) showed a higher Ni2+ uptake capacity than crystalline samples (fired at 900 degrees C). Ni2+ uptake was found to increase with increasing of CaO content. Amorphous 4CaO center dot Al2O3-2SiO(2) showed the highest Ni2+ uptake capacity (about 9 mmol/g). The Ni2+ uptake abilities of the present samples are higher than those of other materials reported in the literature. Since the sorbed Ni2+ released Ca2+ ratios of these samples are close to unity, ion replacement of Ni2+ for Ca2+ is thought to be the principal mechanism of Ni2+ uptake by the present samples. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2005.04.023

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

TiO2 (anatase) coating was prepared on stainless mesh by electrophoretic (EPD) process utilizing an isopropyl alcohol (IPA)-based suspension with submicron TiO2 powder. When the deposition time was 30 s, a smooth thin coating was obtained. It remained crack-free even after sintering. Coating surface morphology was roughened by UV pre-illumination of the suspension. Photocatalytic decomposition of IPA to acetone and resultant electrochemical reaction at cathode during EPD provides heterogeneous deposition. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.materresbull.2005.04.030

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Language：English   Publisher：CLAY MINERALS SOCIETY  

The loading of various phosphates on the surfaces of nanoparticles of allophane (1-2SiO(2)-Al2O3.5-6H(2)O) was investigated. The allophane used was a high-silica type with a Si/Al ratio of 0.85. The phosphate-sorption isotherm was measured using (NH4)(2)HPO4 solution, which showed the highest phosphate sorption of the seven phosphates examined. This sorption isotherm was in better agreement with the Langmuir equation than the Freundlich equation. The resulting maximum sorption capacity was 4.87 mmol/g and the Langmuir constant was 0.0033 L/mmol. The sorption energy (AG) calculated from the Langmuir constant was -2.96 kJ/mol. The amount of loaded phosphate varied greatly according to the phosphate used, being greater for orthophosphates than for polyphosphates. The amount of loaded phosphate also depended on the cation present, in the order Ca-Na-NH4-phosphate. The Si/Al ratios of the samples were decreased by orthophosphate loading due to the partial replacement Of SiO4 by PO4 tetrahedra, but this effect was offset by the partial dissolution of the allophane by polyphosphate loading. The Si-29 magic angle spinning nuclear magnetic resonance (MAS NMR) spectra of all the phosphateloaded samples showed an increase of a peak at -90 ppm (the Q(1)-Q(3) polymerized tetrahedral unit) and the decrease of a peak at -78 ppm peak (the Q(o) monomeric tetrahedral unit). The P-31 MAS NMR spectra showed peaks at similar to-10 ppm, assigned to Q(2) units corresponding to polymerized tetrahedra which consisted of loaded PO4 together with Si(Al)O-4. The structure changes produced in allophane by phosphate loading are discussed in light of these data.

DOI： 10.1346/CCMN.2005.0530405

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Language：English   Publisher：CHEMICAL SOC JAPAN  

The effect of surface roughness on lipophobicity was investigated on a surface prepared using a combination of boehmite nanoparticles and fluoroalkylsilane. The requirement of surface roughness for superlipophobicity by oleic acid is higher than 565 nm when the surface energy is approximately 14 MJ/m(2). This roughness value is around ten times of that for superhydrophobicity.

DOI： 10.1246/cl.2005.908

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Language：English   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

The effect of phosphate grafting on the uptake of various heavy metal ions was investigated using allophane, a clay mineral having a chemical composition of 1-2SiO(2).Al2O3-5(.)6H(2)O with hollow nanoparticles 3.5-5 nm in size. Phosphate grafting was performed on allophane with an atomic ratio Si/Al = 0.85 using the orthophosphates (NH4)(2)HPO4, Na2HPO4 and CaHPO4 and the triphosphate Na5P3O10. The cations in the phosphates were partially retained in the samples, along with the grafted phosphate. Uptake experiments were performed with various heavy metal ions (Cu2+, Zn2+, Ni2+, CO2+, and Mn2+) and alkaline earth ions (Mg2+ and Ca2+) using a batch method. With increasing amounts of grafted phosphate, the Cu2+ uptake capacity increases to about double of that of ungrafted allophane. Although part of the grafted phosphate is released during the uptake experiments, this can be largely suppressed by heat-treating the samples at 200-500 degrees C. The Cu2+ uptake ability of the (NH4)(2)HPO4-grafted sample showed a steep decrease with higher heating temperature according to the thermal decomposition of NH4+. The ratios of cations released from the samples to cations removed from solution (2Na/Cu and Ca/Cu) are close to unity. From these results, the replacement reaction is thought to be the main uptake mechanism of heavy metal ions in the present samples. The uptake abilities of the present samples for various cations are explained with respect to the solubilities of the corresponding metal phosphates. (c) 2005 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2005.01.033

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Language：English   Publisher：ELSEVIER SCIENCE BV  

In the current work, we demonstrate the effect of the microstructure of polycrystalline TiO2 thin films prepared by the sol-gel process on the film's photoinduced hydrophilicity. The TiO2 thin films were prepared with different microstructures but almost the same crystal phase, band gap, film thickness and surface roughness. These films were prepared from the same starting materials, and the surface microstructure was changed by vacuum ultraviolet (VUV) irradiation before firing. The VUV-treated film possessed more heterogeneous microstructure (larger grains) than the non-VUV-treated film. The non-VUV-treated film exhibited a higher hydrophilicizing rate under UV irradiation than the VUV-treated film. Friction force microscopy (FFM) revealed that the relative area of the bright region, namely the hydrophilic region, increased in both films under UV irradiation. However, this contrast change is more homogeneous and remarkable in the non-VUV-treated film than in the VUV-treated film. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.susc.2005.01.035

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Language：English   Publisher：ELSEVIER SCIENCE SA  

Crystallization behavior of sol-gel-based TiO2 precursor films by vacuum ultraviolet (VUV) light illumination was investigated. VUV light illumination induces densification of films. This reaction accompanies the removal of organic compounds and OH groups with increasing apparent coordination number of titanium in the film from five to six. This structure change enhances film crystallization; polycrystalline anatase films were obtained by post annealing at 300 degreesC. Crystallization behavior suggested that proper balance of densification and removal of organic compounds are important tasks for further lowering crystallization temperature. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.surfcoat.2004.04.034

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DOI： 10.11451/mukimate2000.12.435

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Language：Japanese   Publisher：The Surface Finishing Society of Japan  

Enhancement of hydrophobicity by a roughness mixture was investigated on two different model structures. A two-dimensional particle array and commercial embossed film were employed as a bottom rough surface, and a colloidal silica-fluoropolymer composite was coated on these surfaces. Both model surfaces became superhydrophobic by the roughness mixture. These results were quantitatively analyzed based on their surface morphology. The hydrophobicity enhancement was explained by an effective increase of the solid-air interface area.<br>

DOI： 10.4139/sfj.56.925

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Language：English   Publisher：VSP BV  

The correlation between the photocatalytic properties of a batch reactor and those of a flow reactor was investigated. The photocatalytic properties were evaluated using the amount of H2S removed from the gas phase by the TiO2 photocatalytic reaction for both systems. When the reaction was nearly controlled by mass transport, we clarified that the data in the flow system were estimated from those in a batch system by taking account of several reaction conditions (volume, light-irradiated area and reactor type).

DOI： 10.1163/1568567053956572

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Language：English   Publisher：ELSEVIER SCIENCE BV  

This study concerns the utilization of waste steel-making slag, a by-product that contains mainly CaO, Fe2O3 and SiO2. The as-received slag was ground and thermally activated by temperature treatment from 110 to 1000degreesC for 24 h. Although the as-received slag was amorphous, it became partially crystallized during grinding. These crystalline phases were larnite and iron oxide but other crystalline phases also appeared in addition to larnite after calcination. The uptake of Ni2+, PO4 (3-) and NH+4 by the samples was investigated from solutions with initial concentrations of 10 mmol/l. The sample calcined at 800degreesC showed the highest Ni2+ uptake (4.85 mmol/g) whereas the highest simultaneous uptake Of PO4 (3-) (2.75 mmol/g) and NH4+ (0.25 mmol/g) was achieved by calcining the material at 700degreesC. The principal mechanism of Ni2+ uptake is thought to involve replacement of Ca2+ by Ni2+. The mechanism Of PO43- uptake is mainly by formation of calcium phosphate while that of NH4+ involves sorption by the porous silica surface of the samples. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2004.08.004

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Language：English   Publisher：ELSEVIER SCIENCE SA  

Decomposition efficiency of 1,4-dioxane in water was examined by sonophotocatalytic method through comparison of TiO2 and HF-treated TiO2. 1,4-Dioxane is effectively decomposed by combining sonolysis and photocatalysis. This synergistic effect is attributable to effective enhancement of photocatalysis by sonolysis. HF treatment of TiO2 surface enhances its absorption capabilities for both 1,4-dioxane and ethylene glycol diformate (EGDF), while improving the overall decomposition rate of 1,4-dioxane by sonophotocatalytic treatment. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jphotochem.2004.04.013

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Language：English   Publisher：ELSEVIER SCIENCE BV  

The sliding behavior of the water droplets on the silicon surface treated by fluoroalkylsilane was directly observed. Water droplets elongated and contracted during sliding, and inversely corresponded to the change of sliding acceleration. Tilt angle and contact angle hysteresis affected this phenomenon. Lowering the difference in contact angle hysteresis between the pre-sliding state and the equilibrium state during sliding will be one of the approaches for suppressing this elastic motion. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.susc.2004.02.029

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Language：English   Publisher：ROYAL SOC CHEMISTRY  

The photocatalytic oxidation activity and photoinduced hydrophilicity of brookite-rich TiO2 film were compared to those of anatase TiO2 film under ultraviolet (UV) light irradiation. The photocatalytic oxidation activities were evaluated by the initial photodegradation rates of methylene blue and cis-9-octadecenoic acid. The rates for the methylene blue bleaching were nearly identical (-2.2 x 10(-3) Abs min(-1)) for the brookite-rich and anatase films, and the rate for cis-9-octadecenoic acid decomposition on the brookite-rich film was slightly less than that on the anatase one (-0.08 +/- 0.01 mug cm(-2) min(-1) and -0.10 +/- 0.01 mug cm(-2) min(-1), respectively). However, the rate constants for photoinduced hydrophilicity, which were evaluated by the changes in water contact angles (theta) under rather weak UV light irradiation (5 muW cm(-2)), were better for the brookite surface than the anatase one. Moreover, the brookite-rich film became more hydrophilic (theta = 10degrees) than the anatase one (theta = 18) after long time exposure to weak UV light irradiation, and showed a good ability for the photoinduced hydrophilicity.

DOI： 10.1039/b315777f

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DOI： 10.1023/B:JSST.0000047986.92384.42

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DOI： 10.1023/B:JMSC.0000030725.35826.77

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DOI： 10.1023/B:JMSC.0000011510.92644.3f

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DOI： 10.2109/jcersj.112.533

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DOI： 10.2109/jcersj.112.138

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DOI： 10.1023/B:JMSC.0000030725.35826.77

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Language：English   Publishing type：Book review, literature introduction, etc.   Publisher：Ceramic Society of Japan  

Hydrophobic coatings have been applied to various industrial items. However, their expected properties cannot always be obtained for practical use by merely decreasing their surface energies. Various cases require precise design and control of a coating's structure and chemical composition. This paper briefly reviews recent studies of transparent hydrophobic coating design. It specifically addresses superhydrophobic coatings.

DOI： 10.2109/jcersj.112.533

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Language：Japanese   Publisher：エヌ・ティー・エス  

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DOI： 10.1023/B:JMSC.0000011510.92644.3f

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Language：English   Publisher：Ceramic Society of Japan  

Self-organized nanograded SiO2/TiO2/Polymethyl methacrylate (PMMA) thin film was successfully prepared by only one coating from the combination of Tetraethyl orthosilicate (TEOS) and Titanium tetraisopropoxide (TTIP). Sufficient kinetics difference between two alkoxides was an important requirement for the processing of the graded thin film in this process. The film was colorless and transparent due to two gradual interfaces of three layers. The reflectance of the SiO2/TiO2/PMMA graded film was lower than 2% over a wide wavelength range, and this is attributed to the interference of lights reflected from both the SiO2 layer and TiO2 layer. Although further investigation and precise process control are required to further decrease reflectance, this film can be formed using only one coating process and has great potential as a new low reflective coating.

DOI： 10.2109/jcersj.112.138

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DOI： 10.1023/B:JSST.0000047986.92384.42

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Language：English   Publisher：CHEMICAL SOC JAPAN  

The sliding acceleration of a water droplet on a silicon surface treated with octadecyltrichlorosilane was evaluated by changing the droplet weight. All water droplets slide down with a constant sliding acceleration. The slope of the sliding acceleration against the droplet weight was changed at 20 mg, suggesting that the dominant sliding mode was shifted from slipping to rolling.

DOI： 10.1246/cl.2003.1148

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Language：English   Publisher：ELSEVIER SCI LTD  

The effect of CaCO3 addition on the emission of dioxins from poly(vinyl chloride) (PVC) incineration was investigated. It was found that incorporation of CaCO3 greatly reduced the generation of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in the exhaust gas. Although the amount of PCDDs and PCDFs trapped in the ash increased, the total amount (the sum in the gas and ash) decreased significantly after CaCO3 addition. The possible mechanism for the suppressing effect of CaCO3 additive is discussed. The PCDDs and PCDFs trapped in the ash would not become environmental issues because they are expected to be decomposed by the TiO2 photocatalyst, which was simultaneously incorporated in the PVC with CaCO3. (C) 2002 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0141-3910(02)00288-4

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The rate of BrO3- reduction by a commercial TiO2 photocatalyst under UV illumination in an aqueous solution was increased by lowering the pH from 7 to 5. The effect is attributable to an enhancement of the electrical interaction between BrO3- and the positively charged surfaces of the TiO2 photocatalyst. The surface charge can be controlled by a surface modification of the TiO2 photocatalyst without controlling the pH of the water. In fact, the isoelectric point of surface-modified TiO2 was higher than that of the unloaded TiO2 photocatalyst, resulting in an increase in the rate of the photocatalytic reduction of BrO3- at a neutral pH. This increase is explained by an increase in the amount of adsorbed BrO3- on the photocatalyst surface.

DOI： 10.1021/es0258733

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Language：English   Publisher：AMER CHEMICAL SOC  

The rate of BrO(3)(-) reduction by a commercial TiO(2) photocatalyst under UV illumination in an aqueous solution was increased by lowering the pH from 7 to 5. The effect is attributable to an enhancement of the electrical interaction between BrO(3)(-) and the positively charged surfaces of the TiO(2) photocatalyst. The surface charge can be controlled by a surface modification of the TiO(2) photocatalyst without controlling the pH of the water. In fact, the isoelectric point of surface-modified TiO(2) was higher than that of the unloaded TiO(2) photocatalyst, resulting in an increase in the rate of the photocatalytic reduction of BrO(3)(-) at a neutral pH. This increase is explained by an increase in the amount of adsorbed BrO(3)(-) on the photocatalyst surface.

DOI： 10.1021/es0258733

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Language：English   Publisher：ELSEVIER SCIENCE SA  

The photocatalyzed decomposition reaction of gas-phase octamethyltrisiloxane (OMTS) on TiO(2) thin films was investigated in a batch-type photocatalytic reactor. The effectiveness of TiO(2) photocatalyst for decomposing OMTS was demonstrated by the decrease of OMTS concentration and increase of carbon dioxide concentration with illumination time as monitored using a gas chromatography. However, the photocatalytic activity was found to decrease with increasing reaction time, and catalyst deactivation was finally observed on the TiO(2) film that suffered from a long-time reaction. Formation and accumulation of hydroxylated SiO(x) (x = 3 similar to 4) on the irradiated TiO(2) surface were detected by X-ray photoelectron spectroscopic (XPS) measurements. An equivalent amount of similar to7 monolayers of OMTS was estimated to be decomposed on the fully deactivated TiO(2) photocatalyst as calculated from the saturated adsorption value and the total decomposed amount of OMTS. It was found that thus formed SiOx can be easily removed by treatment in an alkaline solution for a short period of time without influencing the underlying TiO(2) film. Regeneration of the photocatalytic activity of the SiO(x)-removed TiO(2) thin film was confirmed by the re-decomposition of OMTS under the same experimental conditions. (C) 2003 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S1010-6030(02)00322-2

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Language：Japanese   Publisher：The Surface Finishing Society of Japan  

A transparent super-hydrophobic polymer film was prepared by the screen printing method. Both urethane particles and colloidal silica were employed as fillers of the paste for printing. Colloidal silica effectively improved the rheological property of the paste and the urethane particles provided proper roughness. By mixing different roughness dimension, transparency, durability and super-hydrophobicity were satisfied in the prepared film simultaneously. This work demonstrated that proper filler selection is one of the key factors for the processing of multi-functional polymer films by the screen printing method.

DOI： 10.4139/sfj.54.677

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Other Link： https://jlc.jst.go.jp/DN/JALC/00232490075?from=CiNii

Language：English   Publisher：AMER CHEMICAL SOC  

The photoinduced hydrophilicity of TiO2 films with underlying WO3 layers (TiO2/WO3 layered thin film) was evaluated. Although the top surface was fully covered by TiO2, the presence of the WO3 layer enhanced the hydrophilic conversion rate under a 10-W cylindrical fluorescent light bulb. When the TiO2 and WO3 layers were separated by an insulating layer, the surface did not become highly hydrophilic under the same light bulb. On a TiO2/WO3 layered film the photocatalytic oxidation of methylene blue adsorbed onto the surface and the photocatalytic reduction of silver nitrate in an aqueous solution were investigated under a 10-W cylindrical black light bulb. The oxidation reaction was enhanced by the presence of the WO3 layer, however the reduction reaction was not. These results indicate that the photogenerated charge carriers can transfer between the TiO2 and WO3 layers, i.e., photogenerated holes accumulate in the TiO2 layer, whereas electrons accumulate in the WO3 layer. Because of the efficient charge separation, a TiO2/WO3 layered film formed on a grounded electroconductive substrate displayed a higher hydrophilicizing rate than when coated onto an insulating substrate. It was also demonstrated that visible light passing through the TiO2 layer could excite WO3. Thus, visible light can be used for the hydrophilic reaction in the present TiO2/WO3 system.

DOI： 10.1021/cm020355c

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Language：English   Publisher：AMER CHEMICAL SOC  

Hydrophobicity and sliding behavior of water droplets were investigated on various hydrophobic pillarlike and groove structures prepared on a silicon wafer by dicing and subsequently coating with fluoroalkylsilane. The dominant hydrophobicity mode was changed from Wenzel's mode to Cassie's mode at a smaller roughness than that expected from the calculation based on the sinusoidal surface by Johnson and Dettre. The effect of water intrusion on the microstructure due to droplet weight was revealed to be an important factor governing the water sliding angle on the surface. In a comparison of the sliding behavior of water droplets over pillarlike and groove structures, it was demonstrated that a proper design of the surface with respect to shape and extent of the three-phase line is more effective than the increase of contact angles merely by decreasing the solid-water contact area.

DOI： 10.1021/la020088p

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Language：English   Publisher：AMER CHEMICAL SOC  

Thin films of various metal oxides were prepared on glass substrates by a wet process to determine their photocatalytic ability to decompose adsorbed dye and to evaluate their photoinduced hydrophilicity under UV illumination. The metal oxides used in this study are classified into four categories based on their behavior over the two photochemical reaction: (1) active in both photocatalytic oxidation and photoinduced hydrophilicity (TiO2, SnO2, ZnO); (2) only active in photocatalytic oxidation (SrTiO3); (3) only active in photoinduced hydrophilicity (WO3, V2O5); (4) and inactive over both processes (CeO2, CuO, MoO3, Fe2O3, Cr2O3, In2O3). X-ray photoelectron spectroscopy revealed that oxygen defect sites were produced by Ar+ bombardment on the surface of metal oxides, showing photoinduced hydrophilicity. These results indicate that photoinduced hydrophilicity is not induced by the photocatalytic oxidation of organic compounds adsorbed on the surface, but is based on structural changes of the metal oxide surfaces.

DOI： 10.1021/cm020076p

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DOI： 10.2109/jcersj.110.186

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Language：English   Publisher：IWA PUBLISHING  

The effects of pH and the surface charge of photocatalyst on photocatalytic reduction of bromate ions in water were examined by using TiO(2) and alumina-loaded TiO(2) photocatalysts. The amount of adsorbed bromate ion on TiO(2) and the reduction rate of bromate ion by the TiO(2) photocatalyst increased with lowering pH. It was suggested that the bromate ion adsorbed predominantly on the positively charged surface sites of TiO(2) at lower pH, which thus promotes the rate of reduction. The iso-electric point of the TiO(2) photocatalyst was shifted to the higher pH region by loading alumina on the TiO(2) surface, which resulted in the increase of the adsorbed amount of bromate on the photocatalyst and the reduction rate of bromate ion by the photocatalyst at neutral pH. It was concluded from these results that the photocatalytic reduction of bromate ion can be promoted by pH control of water or by controlling the surface charge of the photocatalyst by loading alumina without pH control of water.

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Language：English   Publisher：ELSEVIER SCI LTD  

The effect of HF treatment of TiO2 on its adsorption capability for toxic aromatic compounds generated during polymer combustion was studied. Compared with the non-treated TiO2, ca. 3 times higher adsorption capability for dibenzofuran was detected on the HF treated TiO2 at 200 degreesC. Incorporation of HF-treated TiO2 into poly(vinyl chloride) (PVC) resulted in reduced generation of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in the exhaust gas and increased formation of these compounds in the ash when the TiO2/PVC Composite film was incinerated at 450 degreesC. The higher adsorption capability of HF-treated TiO2 for aromatic compounds may partially explain this result. It was found that HF treatment causes increase in the amount of acid sites on the TiO2 surface, which may thus promote its adsorption capability for aromatic compounds because of the enhanced interaction between the surface acid sites and the pi electrons of the aromatic compounds. Importantly, the dioxins trapped on the TiO2 (a well-known photocatalyst) in the ash can be photocatalytically decomposed under artificial ultraviolet light or sunlight, with only harmless TiO2 powder remained eventually, so they would become no environmental problem. We found that HF-treatment gives almost no impact on the photocatalytic activity of the TiO2. (C) 2002 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0141-3910(02)00191-X

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DOI： 10.1016/S0039-6028(02)01551-0

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DOI： 10.1016/S0039-6028(02)02144-1

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DOI： 10.1143/JJAP.41.287

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DOI： 10.1016/S0039-6028(02)01551-0

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DOI： 10.1016/S0039-6028(02)02144-1

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DOI： 10.1143/JJAP.41.287

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Language：English   Publisher：ELSEVIER SCIENCE SA  

The effect of the repeated UV illumination on the photo-induced wettability conversion of TiO2 surface was investigated using rutile single crystal. The hydrophilicizing rate was increased by the repeated UV illumination and this effect was more remarkable on (001) than (110) surface. This crystal plane dependence can be attributed to the differences of the efficiencies of oxygen vacancy creation and the degrees of resultant structural distortion between these two surfaces. These data suggest that the hydrophilicizing process of TiO2 is a kind of photo-corrosion process occurring at the surface. (C) 2001 Published by Elsevier Science B.V.

DOI： 10.1016/S1010-6030(01)00544-5

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Language：English   Publisher：AMER CHEMICAL SOC  

The photoinduced surface wettability conversion reactions of ZnO and TiO2 thin films were investigated by means of water contact angle measurement and X-ray photoelectron spectroscopy. Before ultraviolet (UV) illumination, ZnO and TiO2 films exhibited water contact angles of similar to 109 and similar to 54 degrees, respectively. UV illumination turned both surfaces to highly hydrophilic with water contact angles smaller than 10 degrees, Storage in the dark reconverted the highly hydrophilic films to their original states. Reversible surface wettability conversion reactions were achieved by alternate UV illumination and storage in the dark on both the films. The similar behaviors of wettability conversion observed on ZnO and TiO2 surfaces suggest that they follow a similar conversion mechanism. Preferential adsorption of water molecules on the photogenerated surface defective sites is ascribed to the formation of highly hydrophilic ZnO and TiO2 surfaces. Achievement of highly hydrophilic ZnO and TiO2 surfaces by high-temperature annealing and Ar+ sputtering provided supporting evidence for the explanation that surface defective sites play crucial roles in causing the surface wettability conversion reactions.

DOI： 10.1021/jp002525j

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Language：English   Publishing type：Book review, literature introduction, etc.   Publisher：SPRINGER-VERLAG WIEN  

Films whose water contact angle is higher than 150 degrees have been the subject of great interest and enthusiastic study in recent years. These films, which are called super-hydrophobic, are fabricated by combining appropriate surface roughness with surfaces of low surface energy. Here we briefly review the fundamental theories on the wettability of a hydrophobic rough solid surface, together with recent works on the processing and properties of super-hydrophobic films. Though the practical application of these films is still limited, the obstacles to application are gradually being surmounted, providing a great opportunity for the development of various industrial products.

DOI： 10.1007/s007060170142

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DOI： 10.1023/A:1013199105688

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Language：Japanese   Publisher：広信社  

CiNii Books

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DOI： 10.1023/A:1013199105688

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DOI： 10.1002/1521-4095(200104)13:7<487::AID-ADMA487>3.0.CO;2-L

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DOI： 10.1002/1521-4095(200104)13:7<487::AID-ADMA487>3.0.CO;2-L

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Language：English   Publisher：WILEY-V C H VERLAG GMBH  

Super-hydrophilic titanium oxide films show excellent potential as anti-fogging and self-cleaning surfaces; however, until now these properties have been limited to outdoor applications, since the high wettability condition requires sunlight-intensity UV radiation. Here is reported a novel TiO2/WO3 film (see Figure) that exhibits such a hydrophilic conversion even under regular indoor lighting.

DOI： 10.1002/1521-4095(200012)12:24<1923::AID-ADMA1923>3.0.CO;2-#

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Language：English   Publisher：ELSEVIER SCIENCE SA  

Hard super-hydrophobic thin films were prepared combining a phase separation of tetraethyl orthosilicate (TEOS) induced by the addition of an acrylic polymer, and subsequent fluoroalkylsilane (FAS) coating. The microstructure of the films was crater-like, and the structural dimension depended on the degree of the phase separation. The dominant mechanism of the hydrophobicity of the film was changed from Wenzel's mode to Cassie's mode with increasing surface roughness. The film obtained by proper composition possessed high transmittance in the visible wavelength range and its hardness was almost at the same level as normal silica-based hard coatings. (C) 2000 Elsevier Science S.A. All rights reserved.

DOI： 10.1016/S0040-6090(00)01417-6

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Language：English   Publisher：ELECTROCHEMICAL SOC JAPAN  

It is well known that the amount of physisorbed water molecules decreases by thermal and evacuating treatments at anatase TiO2 surfaces. (1- 3)) However, the initial water contact angle of the anatase TiO2 surface coated on the glass was little changed (from 24 degrees +-/ 1 degrees to 23 degrees +/- 1 degrees) and the hydrophilicity did not change by the heating treatment at 150 degreesC for 1 hour. On the other hand, the value of its initial contact angle increased remarkably (from 24 degrees +/- 1 degrees to 67 degrees +/- 1 degrees), and the TiO2 surface was hydrophobicized by the evacuation at similar to 5x10(-6) Pa. These observations may show that not only the amount of physisorbed water molecules but also the structure, i.e., OH groups of TiO2 surfaces are related to the hydrophilicity. The photo-decreasing rate of the water contact angle under the ultra violet (UV) illumination at the anatase TiO2 surface (the photo-induced hydrophilic conversion rate) increased by the heating treatment at 150 degreesC for 1 hour. However, photo-induced hydrophilic conversion rates were little changed by the evacuating treatment at similar to 5x10(-6) Pa. These results suggest that the photo-induced hydrophilic conversion phenomena are not necessarily affected by the initial amount of physisorbed water molecules.

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Language：English   Publisher：AMER CHEMICAL SOC  

Transparent superhydrophobic thin films with TiO(2) photocatalyst were prepared by utilizing a sublimation material and subsequent coating of a (fluoroalkyl)silane. The transparency of the films decreased with increasing TiO(2) concentration, which was attributed to the size difference of the starting materials. The film with only 2 wt % TiO(2) maintained higher contact angle than the film without TiO(2) after 1800-h outdoor exposure, the accumulation of stain being avoided due to TiO(2) photocatalysis. The films prepared in this study are the first ones that satisfy the requirements of transparency, superhydrophobicity, and long lifetime simultaneously.

DOI： 10.1021/la000155k

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Language：English   Publisher：AMER CHEMICAL SOC  

The photoinduced wettabilities of both water and hexadecane on a polycrystalline anatase TiO(2) thin film were investigated. An amphiphilic surface was produced on the polycrystalline TiO(2) thin film by UV illumination as on the rutile single crystal. Further illumination of the amphiphilic surface increased the hexadecane contact angle gradually and produced a hydrophilic-oleophobic surface. The total energies of the illuminated UV light to produce and terminate the amphiphilic state were independent of the UV light intensity. This wettability change is attributable to the variations of hydrophilicizing rate of TiO(2) grains, and the resultant hydrophilic-oleophobic property may contribute to overall self-cleaning performance of the TiO(2) thin films.

DOI： 10.1021/la0004348

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Language：English   Publisher：AMER CHEMICAL SOC  

Various superhydrophobic films having different surface roughnesses were prepared, and the relationships between the sliding angle, the contact angle, and the surface structure were investigated In the highly hydrophobic region, the sliding angles of water droplets decreased with increasing contact angles. Microstructural observation revealed that surface structures that can trap air are Important for the preparation of low-sliding-angle surfaces. We have also derived an equation that describes relationship between sliding angles and contact angles on superhydrophobic surfaces with roughness. The results calculated on the basis of this equation agreed well with the experimental ones. Moreover, we have successfully prepared a transparent superhydrophobic film whose sliding angle is similar to 1 degrees for a 7 mg water droplet. On this film, there was almost no resistance to the sliding of water droplets. The film obtained satisfies the requirements of superhydrophobicity, transparency, and a low water sliding angle.

DOI： 10.1021/la991660o

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DOI： 10.1016/S1388-2481(00)00006-0

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DOI： 10.1021/cm990556p

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DOI： 10.1016/S1388-2481(00)00006-0

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DOI： 10.1016/S1010-6030(00)00330-0

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Language：Japanese   Publisher：日本太陽エネルギ-学会  

CiNii Books

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Language：Japanese   Publisher：日刊工業新聞社  

CiNii Books

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DOI： 10.1016/S1010-6030(00)00330-0

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DOI： 10.1021/cm990556p

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Language：English   Publisher：ELSEVIER SCIENCE SA  

Antifogging mirror or self-cleaning glass can be realized utilizing photoinduced hydrophilicity of titanium dioxide. Application fields of functional titanium dioxide coating,a is now expanding rapidly not only in applications for glass but also in applications for polymer, metal and ceramic materials. The high hydrophilic surface of TiO2 is interesting also on the standpoint of the basic photon related surface science of titanium dioxide. In order to understand the photoinduced hydrophilic conversion on titanium dioxide coating in details, it is inevitably necessary to understand the relationship between the photo reaction and the surface crystal structure. In this paper, photoinduced hydrophilic conversion was evaluated on the different crystal faces of rutile single crystal and also polycrystalline anatase titanium dioxide to clarify the dependence of the crystal structure on the photoinduced hydrophilic conversion. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-6090(99)00205-9

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DOI： 10.1002/(SICI)1521-4095(199911)11:16<1365::AID-ADMA1365>3.0.CO;2-F

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DOI： 10.1002/(SICI)1521-4095(199911)11:16<1365::AID-ADMA1365>3.0.CO;2-F

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Language：Japanese  

CiNii Books

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DOI： 10.2109/jcersj.104.340

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DOI： 10.2109/jcersj1950.95.1107_1131

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