担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society (ACS)  

DOI： 10.1021/acs.inorgchem.1c02008

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society (ACS)  

DOI： 10.1021/acs.inorgchem.0c03087

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Royal Society of Chemistry (RSC)  

<p>WO₃ and M-doped WO₃ (M = Sn or In) electrochromic films were obtained from aqueous solutions via evaporation-driven deposition. The In–WO₃ films showed a faster electrochromic response than WO₃ and Sn–WO₃ films, and a good cycle stability.</p>

DOI： 10.1039/d1ra00125f

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer New York LLC  

Abstract: When titanium alkoxides are hydrolyzed for preparing coating solutions for titania thin film deposition, chelating and peptizing agents such as acetylacetone and hydrochloric acid, respectively, are employed in order to suppress the formation of precipitates and obtain homogeneous sols. The present work demonstrates that precipitation can be avoided when 2-methoxyethanol is used as solvent for hydrolyzing titanium isopropoxide even without using chelating or peptizing agents. A sol obtained from a simple solution of molar compositions, Ti(OC3H7 i)4:H2O:CH3OC2H4OH = 1:1:25, was demonstrated to be stable in viscosity at least for &gt
1 month. The stability and long pot life of the sol were evidenced in the identical characters including thickness, crystallite size and refractive index and the similar microstructure of the films prepared from the sols aged for 1 and 30 days at room temperature. The formation of homogeneous sol and its long-period stability were thought to result from chelation of the titanium atoms by 2-methoxyethanol molecules. [Figure not available: see fulltext.]

DOI： 10.1007/s10971-018-4715-x

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

We suggest a novel wet coating process for preparing indium tin oxide (ITO) films from simple solutions containing only metal salts and water via evaporation-driven film deposition during low-speed dip coating. Homogeneous ITO precursor films were deposited on silica glass substrates from the aqueous solutions containing In(NO3)(3)center dot 3H(2)O and SnCl4 center dot 3H(2)O by dip coating at substrate withdrawal speeds of 0.20-0.50 cm min(-1) and then crystallized by the heat treatment at 500-800 degrees C for 10-60 min under N-2 gas flow of 0.5 L min(-1). The ITO films heated at 600 degrees C for 30 min had a high optical transparency in the visible range and a good electrical conductivity. Multiple-coating ITO films obtained with five-times dip coating exhibited the lowest sheet (rho(s)) and volume (rho(v)) resistivities respectively of 188 Omega sq(-1) and 4.23 X 10(-3) Omega cm, respectively.

DOI： 10.1021/acs.langmuir.7b00823

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Anatase thin films were prepared on various plastic substrates by our recently developed sol gel transfer technique. Polycarbonate (PC), poly(methyl methacrylate) (PMMA), polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polyether ether ketone (PEEK), and polyvinylidene chloride (PVDC) were employed as plastic substrates. A Si(100) substrate was first coated with a polyimide (PI)/polyvinylpyrroli-done (PVP) mixture layer, and an alkoxide-derived titania gel film was deposited on it by spin-coating. The resulting titania gel film was heated to 600 degrees C, during which the PI/PVP layer decomposed and the gel film was converted into a 60 nm thick anatase film. The anatase film was then transferred from the Si(100) substrate to the plastic substrate. This was achieved by heating the plastic/anatase/Si(100) stack in a near-infrared image furnace to 120-350 degrees C, depending on the type of plastic substrate, under unidirectional pressure. The anatase film cracked during transfer to PE, PP, PEEK, and PVDC substrates but did not crack during transfer to PC, PMMA, and PET substrates. The fraction of the total film area that was successfully transferred was assessed with the aid of image analysis. This fraction tended to be large for plastics with C=O and C-O groups and small for those without these groups. The film/substrate adhesion assessed by cross-cut tape tests also tended to be high for plastics with C=O and C-O groups and low for those without these groups. The adhesion to plastics without C=O or C-O groups could be enhanced and their transfer area fraction increased by oxidizing the native plastic surface by ultraviolet ozone treatment prior to transfer.

DOI： 10.1021/acs.langmuir.6b04142

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

We prepared cupric oxide (CuO) photocathode films by dip coating from Cu(NO3)(2) aqueous solutions containing poly(vinylpyrrolidone) (PVP). The addition of PVP modified the wettability of FTO glass substrates by the aqueous coating solutions, resulting in the formation of CuO coating layers on the substrates. The thermal decomposition of PVP by provided nanoscale pores in the resultant CuO films, and the porosity increased with increasing PVP content. The porous structure thus obtained led to an efficient photocathodic reaction under UV and visible light illumination (wavelength: 300-800 nm). Highly porous CuO films prepared at [PVP] = 0.25 M exhibited the maximum incident photon-to-current efficiency (IPCE) values of 8.7% and 3.9% at 300 and 500 nm, respectively.

DOI： 10.1039/c6ra26590a

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

We prepared tungsten trioxide (WO3) photo electrode films from organic-additive-free aqueous solutions by a low-speed dip-coating technique. The evaporation-driven deposition of the solutes occurred at the meniscus during low speed dip coating, resulting in the formation of coating layer on the substrate. Homogeneous WO3 precursor films were obtained from (NH4)(10)W12O41 center dot 5H(2)O aqueous solutions and found to be crystallized to monoclinic WO3 films by the heat treatment at 400-700 degrees C. All the films showed a photoanodic response irrespective of the heat treatment temperature, where a good photoelectrochemical stability was observed for those heated over 500 degrees C. The highest photoanodic performance was observed for the WO3 film heated at 700 degrees C, where the IPCE (incident photon-to-current efficiency) was 36.2% and 4.6% at 300 and 400 nm, respectively.

DOI： 10.1021/acs.langmuir.6b00377

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.langmuir.5b02929

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2109/jcersj2.123.457

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

Nanostructured SnO particles were produced by aging Sn6O4(OH)(4) in aqueous solutions containing HCl and gelatin at 60 degrees C, where the morphologies of the SnO products depended on the pH value and the gelatin concentration of the solutions. Flower-like and spherical architectures consisting of radially-branched platy units were obtained by the addition of gelatin, where the branching of SnO crystals was promoted with decreasing pH value and with increasing gelatin contents. The branched structures thus obtained could be formed via diffusion-controlled growth of SnO crystals in viscous solutions.

DOI： 10.1039/c4ce01829j

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c4ra16810k

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2109/jcersj2.122.917

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACADEMIC PRESS INC ELSEVIER SCIENCE  

Crystalline SnO particles were obtained from Sn6O4(OH)(4) by the hydrothermal treatment in aqueous solutions containing gelatin at 150 degrees C for 24 h, where the morphologies of the SnO products changed from blocks to layered disks, stacked plates and unshaped aggregates with increasing amount of gelatin in the solutions. Such morphological changes of SnO particles were thought to be attributed to the suppression of the growth of SnO crystals by the adsorbed gelatin. (C) 2014 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jssc.2014.05.023

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

We prepared silica-poly(vinylpyrrolidone) (PVP) hybrid films containing a photoluminescent organic dye, rhordamine 6G (R6G), by low-speed dip-coating, where the spontaneous pattern formation was induced in the films. Stripe patterns arranged perpendicular to the substrate withdrawal direction were spontaneously formed by stick-slip motion at the meniscus during dip-coating, and the film structure (i.e., the film thickness, and the height, width and spacing of stripe patterns) was changed with increasing amounts of volatile solvent (C2H5OH) in solutions (C2H5OH/Si(OCH3)(4) mole ratio(x) = 20-150). As a result of the optimization of the film structure, localized photoluminescence at the stripe patterns was achieved over x = 120. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.colsurfa.2014.03.066

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10971-014-3304-x

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-BLACKWELL  

Sol-gel-derived TiO2 films were prepared by dip-coating from Ti(OC3H7i)(4)-CH3COCH2COCH3-HNO3-H2O-C2H5OH solutions, and the effect of the H2O content in solutions on the crystallization of TiO2 films during the heat treatment at 800 degrees C was discussed. The crystalline phase, crystallite size, grain size, and refractive index of the TiO2 films depended on the H2O/Ti(OC3H7i)(4) mole ratios (x) in the coating solutions. Highly dense and crystalline rutile films were obtained at x=0.5-10, where the crystallites and grains became larger with increasing x. The further increase in x from 10 to 50 reduced the crystallite size and refractive index of the films, where anatase phase appeared at x=30-50.

DOI： 10.1111/jace.12860

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Preparation of silica thin films from perhydropolysilazane (PHPS) at room temperature has attracted much attention because it provides a new way to realize silica thin films in a variety of technologies where any high temperature processes should be avoided. Although silica gel films can also be prepared from alkoxides at room temperature by conventional sol-gel method, they are believed to have low mechanical and chemical durability. However, even such alkoxide-derived silica gel films have possibilities to become more durable via condensation reaction and densification when aged at room temperature. In Order to clarify whether or not PHPS-derived silica thin films have critical superiority on properties, the hardness and chemical durability were compared between PHPS- and alkoxide-derived silica thin films, where PHPS films were exposed to the vapor from aqueous ammonia at room temperature for PHPS-to-silica conversion. Alkoxide-derived silica gel films were found to be densified and hardened when stored in air at room temperature, which resulted in pencil hardness even higher than 9H on Si(100) substrates. However, the ultra-microindentation tests demonstrated that the PHPS-derived films are definitely harder than the alkoxide-derived ones. The PHPS-derived films were also found to have higher chemical durability in water and in aqueous ammonia. Such higher mechanical and chemical durability of the PHPS-derived films was ascribed to their higher density, i.e., more highly condensed states, which was evidenced in infrared absorption spectra. Hard coating performance on plastic substrates was also studied, and the PHPS-derived films were demonstrated to have much higher adhesive strength on polymethylmethacrylate substrates. The in-plane stress measurement demonstrated that the PHPS-derived films have much lower or even negligible tensile stress, which may be one of the causes for such higher adhesive strength.

DOI： 10.1021/am400845y

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-BLACKWELL  

Spin-on perhydropolysilazane (PHPS) thin films were converted into mechanically hard silica thin films by an exposure to the vapor from aqueous ammonia. Infrared absorption and X-ray photoelectron spectroscopic analyses were conducted to clarify the details of the PHPS-to-silica conversion and the nature of the silica thin film products. The PHPS-to-silica conversion was found to proceed rapidly between 2 and 3h of exposure via a reaction-limited process, where the refractive index and the pencil hardness greatly decreased and increased, respectively. Finally, the O/Si mole ratio close to 2 was achieved, which has never been realized in literature for PHPS-derived silica thin films. It was also found that the condensation of Si-OH groups proceeds in films immediately after PHPS hydrolysis, which is similar to the base-catalyzed hydrolysis-condensation reaction of silicon alkoxides. Although the silica thin films obtained had refractive indices similar to that of silica glass, high pencil hardness over 9H on Si(100) substrates, and O/Si mole ratios close to 2, it was concluded that they are nonidentical to silica glass, containing trace amounts of Si-OH and Si-H groups.

DOI： 10.1111/jace.12513

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10971-013-3081-y

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jallcom.2012.11.196

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

Nanostructured CeCO3OH particles were prepared from aqueous solutions and gels containing CeCl3 and biological polymers (gelatin and agar) by the addition of (NH4)(2)CO3 solutions. The morphologies of the CeCO3OH products depended on the kind and concentration of the biological polymers. Sheaf- and cocoon-like CeCO3OH particles of ca. 2 mu m in size consisting of fine particles of ca. 10 nm in diameter were obtained from the precursor solutions containing gelatin. On the other hand, CeCO3OH precipitates with inhomogeneous size and shape were obtained from the precursor solutions and gels containing agar. Such morphological variation of CeCO3OH particles was thought to be due to the suppression of nucleation and growth of CeCO3OH crystals by the biological polymers. The CeCO3OH particles thus obtained were converted to CeO2 particles by the heat treatment at 600 degrees C, and the morphology as well as nanostructure remained during the heat treatment.

DOI： 10.1039/c3ra43580f

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier B.V.  

Sol-gel derived TiO2 films were prepared from the solutions containing Ti(OC3H7i)4, H2O, HNO3 and C2H5OH by dip-coating, and the effects of the processing parameters (the heat-treatment temperature and time, and the H2O contents in the coating solutions) on the crystallization and densification of TiO2 films during the heat treatment in air were discussed. Anatase films were obtained by the heat treatments over 400°C, and the increase in heat-treatment temperature and time led to a decrease in film thickness and an increase in grain size, crystallite size and refractive index of the films. Moreover, the crystal growth and grain growth were promoted with increasing H2O content in the coating solutions during the heat treatments over 500°C, while the crystallization and densification were suppressed by the slow condensation of TiOH species below 400°C at larger H2O contents. © 2013 The Ceramic Society of Japan and the Korean Ceramic Society.

DOI： 10.1016/j.jascer.2013.06.001

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

A versatile technique for fabricating ceramic thin films on plastics has been proposed. The technique comprises (i) the deposition of a gel film by spin- or dip-coating on a silicon substrate coated beforehand with a release layer, (ii) the firing of the gel film into a ceramic film, and (iii) its transfer onto plastics by melting or softening the plastics surface. Reflective anatase and electrically conductive indium-tin-oxide (ITO) thin films were prepared on acrylic resin and polycarbonate substrates. Patterned ITO thin films could also be fabricated on plastics by using a mother silicon substrate with periodic grooves.

DOI： 10.1021/am3019993

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/la3020332

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

We prepared ZrO2 particles from the solutions containing Zr(OC3H7n)(4). H2O, n-C3H7OH and acetylacetone (acac) via solvothermal treatment at 150 degrees C. The particle size and shape depended on the molar composition of the precursor solutions. Micron-sized spheres consisting of cubic and tetragonal ZrO2 with low crystallinity were obtained via hydrolysis of Zr(OC3H7n)(4) modified with acac, and the size of the spheres decreased from 2-10 mu m to 0.5 mu m with increasing amount of H2O and n-C3H7OH at constant n-C3H7OH/H2O mole ratios. The non-aggregated, homogeneous microspheres can be observed even by optical microscopy. The crystallinity of the ZrO2 spheres were improved by the heat treatment at 600 degrees C, and the spherical shape remained during the heat treatment. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.colsurfa.2012.03.065

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10971-011-2649-7

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

An aqueous dip-coating route without using volatile alcohols for preparing dense and porous silica thin films is presented. The films were prepared by dip-coating on Si(100) and silica glass substrates using aqueous suspension of 8-11 nm colloidal silica where no alcohols were added. The addition of polyvinylpyrrolidone (PVP) in the suspension greatly improved the wettability, allowing homogeneous films to be formed on the substrates while the substrates showed poor wettability without PVP. When the as-deposited films were fired at 500-1,000 A degrees C, optically transparent porous films with smooth surface were obtained. The porous films had homogeneous distribution and packing of silica nanoparticles, refractive indices of 1.24-1.33, and pencil hardness lower than 6B. The porous films underwent significant densification by viscous sintering when fired at temperatures over 1,000 A degrees C. The viscous sintering was accompanied by the progress of condensation reaction and by the structural relaxation of siloxane network, which was revealed in the infrared absorption spectra. The resulting dense films had optical transparency, smooth surface, pencil hardness over 9H and refractive indices close to that of silica glass.

DOI： 10.1007/s10971-011-2638-x

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER INST PHYSICS  

The in-plane residual stress in thin films greatly affects their properties and functionality as well as the substrate bending, and hence is an important factor to be controlled. In order to obtain general knowledge on the development of residual stress in sol-gel-derived oxide thin films, the in-plane residual stress was measured for yttria stabilized zirconia gel films on Si(100) wafers as a function of firing temperature by measuring the substrate curvature. The films showed a rather complex variation in residual stress, and the mechanism of the residual stress evolution was discussed, referencing the intrinsic stress and the x-ray diffraction data. At low annealing temperatures of 100-200 degrees C, the residual tensile stress decreased and became compressive partially due to the structural relaxation occurring during cooling. When the firing temperature was increased over 200 degrees C, the residual stress turned tensile, and increased with increasing annealing temperature, which was attributed to the increase in intrinsic stress due to film densification as well as to the reduced structural relaxation due to the progress of densification. The residual tensile stress slightly decreased at firing temperatures of 500-600 degrees C, which was attributed to the reduction in intrinsic stress due to thermally activated atomic diffusion as well as to emergence of thermal stress. At firing temperature over 600 degrees C, the residual tensile stress increased again, which was attributed to the increase in thermal stress generated during cooling due to the increased Young's modulus of the film. Although appearing to be complicated, the whole variation of residual stress with firing temperature could be understood in terms of film densification, structural relaxation, atomic diffusion, progress of crystallization and thermal strain. The illustration presented in the work may provide a clear insight on how the residual stress could be developed in a variety of functional sol-gel-derived, crystalline oxide thin films. (C) 2012 American Institute of Physics. [doi: 10.1063/1.3673330]

DOI： 10.1063/1.3673330

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/jp2094774

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jcrysgro.2011.11.035

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER INST PHYSICS  

A new general route for large area, submicron thick ceramic thin films (crystalline metal oxide thin films) on plastic substrates is presented, where the crystallization of films is guaranteed by a firing process. Gel films are deposited on silicon substrates with a release layer and fired to be ceramic films, followed by transferring onto plastic substrates using adhesives. The ceramic films thus fabricated on plastics exhibit a certain degree of flexibility, implying the possibility of the technique to be applied to high-throughput roll-to-roll processes. Using this technique, we successfully realized transparent anatase thin films that provide high optical reflectance and transparent indium tin oxide thin films that exhibit electrical conductivity on polycarbonate and acrylic resin substrates, respectively. Crystallographically oriented zinc oxide films and patterned zinc oxide films are also demonstrated to be realized on acrylic resin substrates. (C) 2012 American Institute of Physics. [doi: 10.1063/1.3676281]

DOI： 10.1063/1.3676281

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

Linear patterns were spontaneously formed on the silica and titania dip-coating films prepared from tetramethyl orthosilicate (Si(OCH3)(4)) and titanium tetraisopropoxide (Ti(OC3H7i)(4)) solutions, respectively. In both films, the pattern formation occurred at extremely low substrate withdrawal speeds below 1.0 cm min(-1), where the film thickness increased with decreasing substrate withdrawal speed for dip-coating. The linear patterns on micrometre scale were arranged perpendicular to the substrate withdrawal direction. The values of R-Z (10 point height of irregularities) and S (mean spacing of local peaks) of the patterns increased with decreasing substrate withdrawal speed.

DOI： 10.1039/c1ra00770j

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

We prepared crystalline SnO2 particles from aqueous solutions of SnCl4 containing poly(acrylic acid) (PAA) by hydrothermal treatment at 150 degrees C. The morphology of the SnO2 particles depended on the concentration of PAA and the pH value of the precursor solutions. The flower-like SnO2 particles of ca. 100 nm in diameter consisting of needle-like units ca. 50 nm in size were obtained from the solution of [SnCl4 center dot 5H(2)O] = 0.1 M and [PAA] = 0.02 M containing the acidic solvents of pH 0.35 via the hydrothermal treatment. The needle-like units were found to consist of nanorods of ca. 50 nm in length and ca. 5 nm in width. The flower-like SnO2 particles were thought to be formed through the moderate nucleation and growth rates that were provided by the relatively high solubility of the Sn4+ species under the acidic conditions and the their coordination by PAA.

DOI： 10.1039/c2ra01037b

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

We prepared a new class of organicinorganic hybrid materials with high refractive indices and thermoplasticity. Titanium and zirconium alkoxides were hydrolyzed in the presence of β- diketones of high melting and boiling points, followed by concentration and heating over 100 °C. Transparent, glass-like solid materials were obtained, exhibiting softening or melting behavior on heating in spite of the absence of organic polymers. The refractive indices of the thermoplastic hybrid materials were as high as 1.7. © 2012 The Chemical Society of Japan.

DOI： 10.1246/cl.2012.319

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

We prepared silica-poly(vinylpyrrolidone) (PVP) hybrid films via a temperature-controlled dip-coating process and investigated the influence of the coating temperature (i.e., the temperature of substrates, solutions and atmosphere) on the spontaneous pattern formation based on the "coffee-ring effect". Micron-scale stripe patterns were spontaneously formed on the surface of the films at high coating temperatures over 40 degrees C during dip-coating. The stripe patterns were arranged perpendicular to the withdrawal direction, and the height and width of the patterns increased with increasing coating temperature. Such spontaneous pattern formation is attributed to the evaporation-driven capillary flow of coating solutions at the meniscus, and the stripe patterns with larger heights and widths are thought to be achieved by the capillary flow activated at higher coating temperatures.

DOI： 10.1039/c2sm26328a

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Fe2O3-SnO2 coating films of various Sn/(Fe + Sn) mole ratios, r(sn), were prepared by dip-coating on Nesa silica glass substrates from the solutions consisting of Fe(NO3)(3) center dot 9H(2)O, SnCl4 center dot 5H(2)O, H2O, CH3COCH2COCH3, and CH3OC2H4OH. The photoanodic properties were studied in a three-electrode cell with an aqueous buffer solution of pH = 7 as the supporting electrolyte. The Fe2O3-SnO2 films of r(sn) = 0-0.25 comprised hematite phase and exhibited photoresponse under the UV and visible light. The photoanodic response of the alpha-Fe2O3 film was enhanced by doping with Sn4+; the film of r(sn) = 0.1 exhibited the maximum IPCE (incident photon-to-current efficiency) of 26.9% and 8.6% at the wavelengths of 350 and 425 nm, respectively, which were higher than those of the Fe2O3-TiO2 film of Ti/(Fe + Ti) = 0.1 prepared by similar process. IPCE decreased with increasing r(sn) from 0.1 to 0.25. The films of r(sn) &gt;= 0.5 comprised rutile phase without hematite phase, showing very low IPCE.

DOI： 10.1021/jp112279k

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

We prepared crystalline SnO2 particles from aqueous solutions of SnCl4 with and without citric acid via hydrothermal treatment. The crystallinity, the crystallite size and shape, and the morphology of the secondary particles depend on the concentration of citric acid, the pH value of the solvents and the hydrothermal treatment temperature. Spherical SnO2 particles of 1-3 mu m in diameter consisting of nanocrystallites below 10 nm in size were obtained via hydrothermal treatment at 150 degrees C from a solution with the citric acid/SnCl4 mole ratio of 0.5 in acidic solvents of pH 3.0-5.5. The SnO2 spheres were thought to be formed through the moderate nucleation rate provided by the relatively high solubility of Sn4+ species and coordination by citric acid. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jcrysgro.2011.02.002

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2109/jcersj2.119.434

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Linear striations and cell-like patterns were spontaneously formed on the dip-coating Mania films prepared titanium tetraisopropoxide (Ti(OC3H7i)(4)) solutions. Such unique patterns on micrometer scale were arranged parallel to the substrate withdrawal direction. The values of R-z (10 point height of irregularities) and S (mean spacing of local peaks) of the patterns increased with increasing film thickness depending on the substrate withdrawal speed for dip-coating, the viscosity of the coating solutions, and the distance front the top edge of films. The shape of patterns changed from linear striations to cell-like patterns with increasing viscosity of the coating solutions. Although the heat treatment at 600 degrees C reduced the height (R-z) of stripes and cells without the change in spacing (S), the visibility of patterns was enhanced by the increase in refractive index due to the crystallization of films.

DOI： 10.1021/la1009708

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CHEMICAL SOC JAPAN  

Formation of anatase spheres was achieved via hydrolysis of Ti(OC3H7i)(4) modified with acetylacetone (acac) under solvothermal conditions at 150 degrees C. The reduction in the degree of hydrolysis by the modification of Ti(OC3H7i)(4) with acac led to the formation of a spherical shape. The 1-5 mu m in diameter spherical particles consisted of anatase nanocrystals below 10 nm in size.

DOI： 10.1246/cl.2010.445

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Olivine-type LiFePO4 crystals were prepared from a precursor phase Fe-3(PO4)(2)(H2O)(8) by a reaction with LiOH under a hydrothermal condition. Particular rod-like units assembled in the same crystallographic orientation were formed in association with L-(+)-ascorbic acid as a reducing and capping agent. Fagot-like mesocrystals were constructed with the oriented rods through parallel growth by supplying abundant Fe2+ and PO43- ions from the precursor phase. An increase in the concentration of the organic additive decreased the unit size, and sheaf-like mesocrystals of LiFePO4 nanorods with high crystallinity and porous structure were obtained

DOI： 10.1021/cg901457t

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

Tin monoxide (SnO) nanosheets 5 nm in thickness are generated on substrates through an aqueous solution process under mild conditions. Parallel control of the oxidation state and morphology is achieved by a urea-mediated approach in aqueous solution. The SnO nanosheets form a porous thin film on substrates such as indium tin oxide and carbon nanofiber (CNF). The porous thin film of SnO nanosheets shows cathodic photo-current generation upon irradiation by UV and visible light. In contrast, the photocurrent is not observed in the bulk SnO microcrystals. Composites of the SnO nanosheets and CNF perform as the anode material of lithium-ion batteries with improved charge discharge reversible stability.

DOI： 10.1002/smll.200902207

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SCIENTIFIC PUBLISHERS  

The photocatalytic activity of a nanostrcutured rutile consisting of oriented nanoneedles was studied by comparing a reaction of a thiazin dye, methylene blue, with dispersed rutile nanoneedles and anatase nanoparticles. Demethylation of methylene blue occurred preferably through partial oxidation under UV irradiation with the bundled rutile nanoneedles having small clearance gaps. On the other hand, most of the dye molecules were directly decolorized through the initiation by a reductive pathway with the dispersed rutile nanorods and the anatase nanoparticles. The reductive sites on (110) of the rutile nanoneedles were dominantly located in the small gaps inside the bundled architecture. Because the diffusion of large-sized organic molecules to the reductive sites would be restricted, the oxidative route for the dye molecule was selectively induced with the rutile bundles under UV irradiation.

DOI： 10.1166/sam.2010.1078

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

We have studied the aqueous solution synthesis of divalent tin oxide (SnO) nanostructures, changes in their optical absorption behavior, and their photoelectrochemical properties. A number of SnO nanostructures including sheets and wires, and their composite morphologies were obtained in aqueous solution containing urea at low temperatures. Parallel control of both oxidation state and morphology was achieved through the urea-mediated solution process. Nanoscale morphological variation facilitated changes in optical absorption behavior and the generation of a photocurrent. As for the nanostructured SnO, the absorption of visible light decreased and absorption in UV region increased. In contrast, bulk black SnO crystals showed strong absorption over the entire range of UV to visible light. A photocurrent was generated from the SnO nanostructures with irradiation of UV and visible light.

DOI： 10.1039/c0nr00370k

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-BLACKWELL  

We have synthesized spinel type cobalt-doped LiMn2O4 (LiMn2-y,CoyO4, 0 &lt;= y &lt;= 0.367), a cathode material for a lithium-ion battery, with hierarchical sponge structures via the cobalt-doped MnCO3 (Mn1-xCoxCO3, (0 &lt;= x &lt;= 0.204) formed in an agar gel matrix. Biomimetic crystal growth in the gel matrix facilitates the generation of both an homogeneous solid solution and the hierarchical structures under ambient condition. The controlled composition and the hierarchical structure of the cobalt-doped MnCO3 precursor played an important role in the formation of the cobalt-doped LiMn2O4. The charge discharge reversible stability of the resultant LiMn1.947Co0.053O4 was improved to ca. 12% loss of the discharge capacity after 100 cycles, while pure LiMn2O4 showed 24% loss of the discharge capacity after 100 cycles. The parallel control of the hierarchical structure and the composition in the precursor material through a biomimetic approach, promises the development of functional materials under mild conditions.

DOI： 10.1002/asia.200900494

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ssi.2009.04.016

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Crystallographically oriented yet morphologically squiggly nanoscale ZnO architecture was produced through epitaxial growth by using a simple aqueous solution system. Specific adsorption of pyranine, an organic dye molecule having three sulfonic groups, suppressed regular growth in the c direction, and thus induced lateral growth of winding ZnO nanowires with diameters ranging from 20 to 100 rim on a single-crystalline ZnO (001) substrate. Although resultant wool-like structures consisted of tangled wires, the crystalline lattice of the whole architecture was found to be continuous and have six-fold symmetry originating from the single-crystalline substrate. (C) 2009 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.117.255

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

We demonstrated nanostructural control of a functional material for electrochemical applications by using a biomimetic solution route. A nanoscopically ordered architecture of calcite-type MnCO3 nanocrystals mimicking hierarchical structures of biological CaCO3 was successfully produced in an organic gel matrix. A highly porous structure of spinel-type LiMn2O4 was produced as a cathode material for lithium-ion batteries from the ordered MnCO3 architecture through nanocrystalline Mn2O3 as an intermediate phase. The rigid framework consisting of connected LiMn2O4 nanoparticles provided high durability in a lithium insertion/extraction process at a high current density due to a high porosity for the electrochemical reaction and three-dimensional channels for ion diffusion.

DOI： 10.1039/b900397e

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

Photoluminescence depending on nitrogen concentration was investigated using anatase-type TiO2 prepared by the calcination of a mixture of titanyl sulfate hydrate and urea. The substitutional ratio (x) of nitrogen in TiO2 was successfully varied from 0.004 to 0.022 by changing the molar ratio of the mixture. The absorbance at 380-560 nm due to the formation of mid-gap states was proportional to the substitutional ratio of nitrogen controlled by the preparation conditions. In contrast, the fluorescent intensity at 382 nm originating from the band-to-band transition monotonically decreased with an increase in the substitutional ratio with an expansion of the anatase lattice. On the other hand, the maximum intensity of photoluminescence at 560 nm excited at 350 nm, which could be associated with the transition from the conduction band to the mid-gap states, was observed at x = 0.01. The optimal substitutional ratio for the emission was almost agreed with that for the photocatalytic decomposition of methylene blue and acetaldeyde under visible-light illumination. The photoluminescence was fundamentally determined by the balance between photoexcitation originating from a sufficient number of mid-gap states and deactivation of excited electrons and holes due to lattice distortion or defective states induced with the nitrogen doping. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matchemphys.2008.04.053

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Crystalline SnO grown in a Sn6O4(OH)(4) matrix exhibited hierarchical architectures, such as stepped bipyramids, stacked meshes, and rosettes, which were not categorized into the classical assortment of crystal morphologies. The complex architectures consisting of small building units were found to be produced through stacking and/or branching growth accompanied with a decrease in the unit size and degradation of the crystallographic symmetry in their assembly. This particular morphological evolution is presumed to be achieved by increasing the driving force of crystallization in the presence of abundant precursor species supplied from the matrix.

DOI： 10.1021/la800955r

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Novel nanoarchitectures of SnO and SnO2 crystals that had two- and three-dimensionally meshed structures consisting of nanoribbons were prepared through Sn6O4(OH)(4) as an intermediate state. Two-dimensional meshes consisting of oriented nanoribbons of single-crystalline tin monoxide (SnO) that was 50-300 nm wide were grown via Sn6O4(OH)(4), which was initially produced at room temperature. Textured spherical particles with three-dimensional meshed nanostructures were produced at 60 degrees C in the presence of citric acid in the aqueous system. The formation of the specific architectures is ascribed to the densely branching growth of SnO crystals in a matrix of Sn6O4(OH)(4) as a reactant. The meshed nanostructures of rutile-type tin dioxide were successfully obtained by oxidation of the SnO crystals without deformation of their architectures.

DOI： 10.1021/cg070205k

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

The oxidation state of tin oxide crystals grown in an aqueous solution of Sn( II) was successfully controlled. Rutile-type SnO2 and tetragonal SnO were selectively produced under acidic conditions below pH 3.3 and alkaline conditions above pH 13.1, respectively. The nanostructures, including the grain size and shape, and the mesoscopic assembled states of the crystals were changed with the concentration of the Sn( II) species and a subtle variation of the pH. This versatile fabrication process for functional oxides is based on the difference in the stability of Sn( II) and Sn(IV) depending on the pH in an aqueous solution system.

DOI： 10.1021/cg060328p

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

The nanoscale combination of crystalline titania and mesoporous silica particles was successfully applied as a photocatalytic adsorbent for the rapid removal from air and complete decomposition of organic molecules. The composites consisted of anatase particles ca. 7 nm in diameter and mesoporous silica particles 10-100 nm in diameter, which provided a specific surface area of more than 1000m(2)/g. The composites were prepared through the assembly of surfactant micelles and siliceous species in the presence of the titania nanoparticles. Acetaidehyde was quickly removed from air due to the large surface area of the mesoporous silica and then was gradually decomposed into carbon dioxide under UV illumination with mass transfer between the adsorbent and the titania photocatalyst. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.mseb.2005.08.007

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

Nanoscale grains of crystalline TixSn1-xO2 were directly grown over the whole range of [Ti]/([Ti] + [Sn]) ratio (x = 0.00-1.00) in aqueous solutions at near room temperature.

DOI： 10.1039/b511223k

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1046/j.1444-2906.2001.00318.x

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開催地：Liege, Belgium  

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開催地：Warsaw, Poland  

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開催地：Wisby, Sweden  

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開催地：Osaka, Japan  

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開催地：Madrid. Spain  

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開催地：Madrid. Spain  

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開催地：Osaka, Japan  

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開催地：Madrid. Spain  

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開催地：Madrid. Spain  

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開催地：Osaka, Japan  

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開催地：Osaka, Japan  

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開催地：Boston, USA  

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開催地：Miskolc, Hungary  

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開催地：Penang, Malaysia  

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開催地：Penang, Malaysia  

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開催地：Yokohama, Japan  

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開催地：Dresden, Germany  

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開催地：San Francisco, USA  

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