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.  

The electrochemical performance of layered Ni0.8Cu0.2/Ce0.8Gd0.2O1.9 (GDC) cermet anodes is investigated for intermediate-temperature solid oxide fuel cells (IT-SOFCs) at 600 °C using humidified (3% H2O) model syngas with a molar ratio of H2/CO = 3/2 as the fuel. From the results obtained, the electrochemical performance of the functionally graded multi-layered anodes is found to be superior to the mono-layered anodes. The test cell with a bi-layered anode consisting of 100 mass% Ni0.8Cu0.2/0 mass% GDC (10M/0E) and 70 mass% Ni0.8Cu0.2/30 mass% GDC (7M/3E) exhibits high power density. The test cell with a tri-layered anode consisting of 10M/0E, 7M/3E, and 50 mass% Ni0.8Cu0.2/50 mass% GDC (5M/5E) exhibits an even higher power density, suggesting that 10M/0E and 5M/5E layers contribute to the current collecting part and active part, respectively.

DOI： 10.1016/j.jpowsour.2018.04.051

Web of Science

Scopus

researchmap

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 Society of Japan  

In this paper, the photocatalytic activity of nitrogen-doped TiO2/montmorillonite composite (NTM) was successfully enhanced by modification with carbon. NTM was made by mixing a swelling clay solution with an N-doped TiO2 solution prepared by hydrolysis of titanium tetraisopropoxide with urea. Carbon-modified Ndoped TiO2/montmorillonite composite (CNTM) was obtained by grinding the dried NTM with EtOH for 1 h, followed by calcination at 250°C in the air for 2 h. Both NTM and CNTM exhibited visible light absorption in the UVvis spectrum in the same way as commercial NTiO2 powder. Additionally, CNTM greatly extended the absorption edges to the visible light region. The photocatalytic performance of NTM and CNTM was evaluated using a degradation of bisphenol-A under visible light (&gt
420 nm) radiation. Although the commercial TiO2 powder showed less photocatalytic activity under visible light radiation, NTM, CNTM and commercial NTiO2 powder showed high photocatalytic activity. The order of degradation performance was as follows: CNTM &gt
commercial NTiO2 powder &gt
NTM. Since the TiO2 content of CNTM is ca. 30 mass% by energy dispersive spectrum analysis, it was suggested that CNTM has extremely high visible light activity.

DOI： 10.2109/jcersj2.17235

Web of Science

Scopus

researchmap

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 Society of Japan  

The performance of Ni-based trimetallic alloy cermet anodes, Ni0.8-xCu0.2Mx (M = Fe and Co
x = 0.1, 0.2, and 0.3)/ Ce0.8Sm0.2O1.9 (SDC), was investigated for intermediate-temperature (500700° C) solid oxide fuel cells (IT-SOFCs), using humidified (3% H2O) model syngas with a molar ratio of H2/CO = 3/2 as the fuel. Though doping Fe or Co 10 mol% into the Ni0.8Cu0.2/SDC anode led the cell performance to the increase, the cell performance decreased as Fe or Co content increased further. On the one hand, doping Fe or Co into the Ni0.8Cu0.2/SDC anode further effectively inhibited carbon deposition owing to CO on the anode. Our results suggest that the Ni0.7Cu0.2Fe0.1/SDC and Ni0.7Cu0.2Co0.1/SDC anodes are more promising materials than Ni0.8Cu0.2/SDC anode for syngas fuel in IT-SOFCs.

DOI： 10.2109/jcersj2.17110

Web of Science

Scopus

researchmap

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  

A power generation system consisting of an intermediate-temperature solid oxide fuel cell (IT-SOFC) and an external reformer for biogas is developed, and its performance is investigated for advanced use of effective biogas. The IT-SOFC is fueled with syngas produced via biogas reforming, and is successfully operated at 600 and 700 degrees C using Ni0.8Cu0.2 alloy/gadolinia-doped ceria electrolyte (Ni0.8Cu0.2/GDC) cermet anodes and a LaAlO3 supported-Ni (Ni/LaAlO3) catalyst. The Ni/LaAlO3 catalyst stably exhibits high reforming performance for effective biogas at 800 degrees C for 27 h, and carbon deposition on the catalyst is prevented. The electrochemical performance of the Ni0.8Cu0.2/GDC cermet anode using syngas fuel possessing a H-2:CO ratio of approximately 3:1 is comparable to the performance achieved with H-2 fuel; the anode remains stable after 24 h of operation at 700 degrees C without interruption and is unaffected by carbon deposition. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jpowsour.2016.11.080

Web of Science

researchmap

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

Ni-based alloy cermet anodes,Ni1-xCux (x = 0.0, 0.2, 0.5, and 1.0)/Ce0.8Sm0.2O1.9 (SDC), were prepared for use with syngas fuel in intermediate-temperature solid oxide fuel cells by in situ reduction of Ni1-xCuxO compounds. The electrochemical performances of cells with the Ni1-xCux/SDC anodes were investigated at 700 and 600 degrees C, using humidified (3% H2O) syngas with H-2/CO = 3/2 as the fuel. Cu doping of the Ni/SDC anode effectively suppressed carbon deposition on the anode. However, the cell performance was deteriorated with increasing amounts of Cu. The Ni0.8Cu0.2/SDC anode was found to be promising for use with syngas fuel. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ijhydene.2016.05.070

Web of Science

researchmap

記述言語：英語  

DOI： 10.1016/j.jascer.2015.04.003

researchmap

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

BaTi1-xSnxO3-supported Ni-based catalysts recovered from spent Ni-metal-hydride (NiMH) batteries [wNi/BaTi1-xSnxO3 (x = 0.0, 0.2, 0.4, 0.6, and 1.0)] were prepared. Their catalytic activities for model biogas reforming reactions were examined at 800 degrees C and compared with that of wNi/gamma-Al2O3. According to the results, wNi/BaTi0.8Sn0.2O3 exhibited high reforming performance and high sustainability among the catalysts tested. wNi/gamma Al2O3 exhibited unsustainability due to carbon deposition, although its performance was excellent for a short time. BaTi0.8Sn0.2O3 functioned as an inhibitor, depressing carbon deposition. This function was likely due to the mobile oxide ions and alkaline earth oxides in the catalyst supports. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ijhydene.2015.04.106

Web of Science

researchmap

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  

The present work demonstrates a novel separation technique by ZSM-5 zeolite bulk bodies, which were successfully prepared with a one-pot hydrothermal method at 200 degrees C for 5 d, using the raw materials that are used in the synthesis of ZSM-5 powders. It is found that these materials can efficiently concentrate a 5 mass% ethanol/water mixture by vapor permeation at approximately 5 kPa to produce a permeate of approximately 76 mass% at an extremely large flux of about 35 kg.(m(2) h)(-1), even though they are porous. The permeate flux is unchanged for a long time. These bulk bodies show promise as materials for the innovative energy-efficient separation of ethanol/water, especially compared with the membranes previously used for such separations. Furthermore, they can efficiently concentrate 5 mass% methanol/water and 2-propanol/water mixtures. (C) 2015 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.micromeso.2015.01.046

Web of Science

researchmap

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  

We have investigated a photocatalytic ozonation system of seven metal oxide semiconductors, TiO2 (P25), Nb2O5, SnO2, WO3, Fe2O3, In2O3, and BiVO4, under visible light both with and without UV irradiation for their efficacy in removing total organic carbon (TOC) from aqueous oxalic acid solution for water treatment. The investigation revealed that all the metal oxide samples functioned as photocatalysts for the photocatalytic ozonation system. TiO2 exhibited the highest activity under UV irradiation, and also exhibited a little activity under visible light irradiation. WO3, Fe2O3, In2O3, and BiVO4 functioned as visible-light-responsive photocatalysts and Fe2O3, In2O3, and BiVO4 were newly identified as active photocatalysts under visible light irradiation for the photocatalytic ozonation system. It is suggested that WO3 is a promising material for the photocatalytic ozonation system due to its activity in the wavelength range of solar energy. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cej.2014.11.088

Web of Science

researchmap

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  

Ultraviolet (UV)-irradiated titanium dioxide (TiO2) photo-catalyst surfaces exhibit excellent oil repellency and therefore an oil droplet cannot adhere to its surface in water even when tightly pressed to it. Ultrasonic irradiation treatment in water greatly decreases the degree of underwater oleophobicity, allowing the oil droplet to adhere to the surface in water. We demonstrate that UV and ultrasonic irradiation treatment can be used to reversibly change the underwater oil repellency of TiO2 surfaces.

DOI： 10.1246/cl.140981

Web of Science

researchmap

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  

A robust rough titanium dioxide (TiO2) surface was prepared by acid treatment of a Ti plate and mesh. By ultraviolet (UV) irradiation, the surface exhibited superhydrophilicity and superoleophilicity in air and underwater superoleophobicity. Due to the rough surface, the underwater superoleophobicity was observed, even after dark storage for 1 week under the ambient atmosphere. The robust rough TiO2 mesh with a pore size of approximately 150 mu m functioned as a high speed oil/water separation filter with high mechanical durability and self-cleaning property. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.colsurfa.2014.10.009

Web of Science

researchmap

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  

We investigated the self-cleaning efficiencies of titanium dioxide (TiO2) surface under ultraviolet (UV) irradiation in combination with a water flow (UV/water) condition using oleic acid as the model surface contaminant. UV light intensities were varied from a typical indoor intensity level to a representative outdoor intensity level in Japan. The combined UV/water treatment exhibited a much higher self-cleaning efficiency than either condition alone. This suggests that the self-cleaning effect occurred at nanometer-sized photo-induced superhydrophilic domains of the TiO2 film surface located at the interface of the TiO2 surface, oleic acid, and air. (C) 2014 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.122.513

Web of Science

researchmap

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  

Rough nanostructured anatase TiO2 surfaces containing many pores were prepared by the hydrothermal-based method. Surface modification with self-assembled monolayers (SAMs) of octadecylphosphonic acid (ODP) resulted in the superhydrophobic surface with an extremely high static water contact angle (CA) of 173.6 degrees +/- 1.7 degrees. This superhydrophobic surface could be converted into a superhydrophilic surface with a water CA of nearly 0 degrees by irradiating it with ultraviolet (UV) light, which induced photocatalytic decomposition of the ODP SAM. A superhydrophobic-superhydrophilic pattern with an extremely high wettability contrast (a water CA difference of over 170 degrees) could be fabricated on the ODP-modified TiO2 surface by area-selective UV irradiation through a photomask. This is the report of the TiO2-based superhydrophobic-superhydrophilic pattern with a water CA difference of over 170 degrees, and it may be possible to use such patterns for various applications. (C) 2014 Elsevier B. V. All rights reserved.

DOI： 10.1016/j.tsf.2014.02.060

Web of Science

researchmap

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  

TiO2 nanotube arrays prepared by the anodization of Ti plate exhibited underwater superoleophobicity. The surface almost completely repelled the oil droplet in water, even after storage in dark for one week under ambient conditions. The TiO2 nanotube arrays fabricated on a Ti mesh were found to be useful as oil-water-separation filters.

DOI： 10.1246/cl.131155

Web of Science

researchmap

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  

Al-substituted 11 angstrom-tobermorite was formed by alkaline hydrothermal treatment of blast furnace slag with sodium silicate added at 180 degrees C for 2-48 h. Effects of the hydrothermal treatment time were characterized by XRD, SEM, and isothermal adsorption of N-2. Sorption characteristics of the obtained samples were examined for Cs+ and Sr2+. The sample obtained by hydrothermal treatment for 48 h (HT-48 h) consisted of calcium silicate hydrate (C-S-H), and Al-substituted 11 angstrom-tobermorite. The HT-48 h showed the highest performance for Cs+ and Sr2+ selectivity in the presence of Na+. The interlayer Na+ of Al-substituted 11 angstrom-tobermorite and surface Ca2+ played an important role in selective Cs+ and Sr2+. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2013.12.024

Web of Science

researchmap

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  

Catalysts based on Zr-O material were prepared from zirconium oxychloride and zirconium oxynitrate with ultrasonication. The deposited Zr-O materials were not detected by XRD because of amorphous phase of an oxygen deficient type zirconia. The obtained zirconia based composite showed higher catalytic performance for oxygen addition activity than Pd based composite for the combustion of carbon. However, the obtained zirconia based composite showed the less catalytic performance for dehydrogenation reaction activity than Pd based composite for the combustion of methane. This zirconia based catalyst is expected to use for the electrode material of the fuel cell that needs restraint of the carbon deposition. (C)2014 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.122.44

Web of Science

researchmap

記述言語：英語   出版者・発行元：日本粘土学会  

Intercalation behavior of acetylsalicylic acid (ASA) to interlayer of hydrotalcite (HT) was investigated in various organic solvents to synthesize ASA/HT composite. ASA intercalation to the interlayer of HT did not occur in an aprotic solvent like acetone but occurred in a protic solvent like alcohols. In the case of alcohols used for solvent, the intercalation behavior was revealed to depend on the alcohol's type. In the primary alcohol (methanol, ethanol, 1-propanol, 1-butanol, and i-butanol), the acetylsalicylate ions were not intercalated, but the salicylate ions were intercalated into the interlayer of HT because of the complete decomposition of ASA in the solution. Since ASA decomposed partially in the secondary alcohol (2-propanol and 2-butanol), the both acetylsalicylate and salicylate ions were intercalated into the interlayer of HT. On the other hand, the decomposition of ASA was substantially restricted in the tertiary alcohol (tert-butanol) because of the stability of the tertiary alcohol. As a result, the acetylsalicylate ions were found to intercalate into the interlayer of HT over 80 mol% and ASA/HT composite was successfully obtained using tert-butanol as solvent.

DOI： 10.11362/jcssjclayscience.18.3_63

CiNii Article

CiNii Books

researchmap

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

The purpose of this study is to clarify the physicochemical properties of Ti2O3 for hydrogen production. The hydrogen production properties of Ti2O3 before and after milling in pure water were investigated in a flat-bottomed reaction vessel made of a Pyrex glass cell which was attached to a closed-gas circulation system under an Ar atmosphere at room temperature using three different types of stirring rod. Ti2O3 was found to be a new material for mechano-chemical hydrogen production, although it did not exhibit photocatalysis or mechano-catalysis for hydrogen production. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ijhydene.2013.09.118

Web of Science

researchmap

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

Nickel (Ni) nanoparticles were synthesized in micropores of zeolite by the adsorption and decomposition of a sublimated Ni organometallic compound, Ni(C5H5)(2), to invent metallic catalysts with nanosize, which are smaller than 5 nm and keep the nanosize at high temperature. In the decomposition process, Ni species were partially decomposed by ultraviolet light irradiation and fixed in zeolite pores prior to thermal reduction under H-2 flow. Note that the Ni nanoparticles showed an excellent thermal stability, because they kept the high dispersion with diameters smaller than 5 nm even after heating at 400 degrees C. On the other hand, the Ni particles supported on zeolite by a conventional method, which is an incipient wetness impregnation process, became larger than 10 nm after heating at the same temperature. The synthesized Ni nanoparticles acted as a metallic catalyst because they showed higher selectivity for H-2 generation than C2H4 generation during ethanol steam reforming reaction. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ijhydene.2013.08.027

Web of Science

researchmap

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 photoinduced wettabilities of water, n-hexadecane, dodecane, and n-heptane on a flat TiO2 surface prepared by a sol gel method-based coating were investigated. An amphiphilic surface produced by UV irradiation exhibited underwater superoleophobicity with an extremely high static oil contact angle (CA) of over 160 degrees. The TiO2 surface almost completely repelled the oil droplet in water. A robust TiO2 surface with no fragile nanomicrostructure was fabricated on a Ti mesh with a pore size of approximately 150 mu m. The fabricated mesh was found to be applicable as an oil/water separation filter.

DOI： 10.1021/la401382g

Web of Science

researchmap

記述言語：英語  

Self-cleaning methods currently employed are based on understanding of the functions, structures, and principles of various objects found in living nature. Three types of surfaces, including superhydrophobic, superoleophobic, and superhydrophilic, offer solutions to keep a surface clean. In this review article, an overview of self-cleaning surfaces inspired by nine biological objects is provided: lotus leaves, rice leaves, cicada wings, butterfly wings, snail shell, fish scale, shark skin, pitcher plant, and photosynthesis. These surfaces exhibit special properties such as low adhesion, low drag, anisotropic wetting, anti-reflection, directional adhesion, anti-fouling, photocatalysis, self-sterilizing, and anti-fogging. We discuss the differences between the superhydrophobic and superhydrophilic surfaces and perspectives for self-cleaning surfaces in the future. © 2013 The Royal Society of Chemistry.

DOI： 10.1039/c2ra21260a

Web of Science

Scopus

researchmap

researchmap

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  

K2NiF4-type Pr2NiO4 doped with Cu, Cu-Ga, or Co (Pr2Ni0.9Cu0.1O4, Pr2Ni0.75Cu0.25O4, Pr1.91Ni0.71Cu0.24Ga0.05O4, or Pr2Ni0.9Co0.1O4) were synthesized by a solid-state reaction for use as cathodes in an intermediate-temperature (500-700 degrees C) solid oxide fuel cell (IT-SOFC). Pr2NiO4, Pr2Ni0.9Cu0.1O4, Pr2Ni0.75Cu0.25O4, Pr1.91Ni0.71Cu0.24Ga0.05O4 and Pr2Ni0.9Cu0.1O4 crystallize in the space group Bmab. Single test cells with samarium oxide doped ceria (SDC) as the electrolyte, Ni-SDC cermet as the anode, and the above-mentioned cathode material were fabricated for cell performance measurements at 700 degrees C. Current interruption measurements and electrochemical impedance spectroscopic analysis revealed that the cathode properties of Pr2NiO4, Pr2Ni0.9Cu0.1O4, Pr2Ni0.75Cu0.25O4, and Pr1.91Ni0.71Cu0.24Ga0.05O4 were comparable to that of La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) and the cathode properties of Pr2NiO4 were improved by doping with Cu or Cu-Ga at the Ni site of Pr2NiO4. (C)2012 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.120.534

Web of Science

researchmap

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  

The fabrication of large ZSM-5 bulk bodies by a hydrothermal method was investigated. The results reveal that porous ZSM-5 bulk bodies with sizes of the order of centimeters could be prepared by the one-pot hydrothermal method using raw materials for synthesizing ZSM-5 powder. Machinability tests and mechanical strength measurements suggest that the bulk bodies obtained are promising as practical materials.

DOI： 10.1246/cl.2012.1414

Web of Science

researchmap

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  

A novel method for determining the carbonate ion contents in layered double hydroxides (LDHs) was demonstrated by FTIR spectrometry. Deconvolution using a curve-fitting technique was performed on the FTIR spectra of LDHs containing both carbonate and carboxylate ions in the interlayer. The contents of carbonate ion calculated from the FTIR spectra were in accordance with those obtained from the chemical composition analysis.

DOI： 10.1039/c2ay25850a

Web of Science

researchmap

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  

A coaxial nanohybrid consisting of a single- walled carbon nanotube (SWCNT), fullerodendron, and SiO(2) shows higheffi ciency light- driven hydrogen evolution from water. Upon visible light irradiation, SWCNT/ fullerodendron/SiO(2) coaxial nano hybrid shows hydrogen evolution activity in the presence of methyl viologen (MV(2+)), benzyldihydronicotinamide (BNAH), and a colloidal polyvinyl alcohol(PVA)-Pt.

DOI： 10.1002/adma.201103472

Web of Science

researchmap

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

The effect of the basicity of zeolite as a metallic catalyst substrate on ethanol steam reforming reaction was investigated. Catalysts with various basicities were prepared using an ion exchange process with aqueous solutions including Na+, K+ and Cs+ after an impregnation process of Ni on Na-Y zeolite (referred to as Ni/Na-Y, Ni/K-Y and Ni/Cs-Y, respectively). Infrared spectroscopy indicated that the OH bonds of ethanol molecules adsorbed on zeolites were weakened with increasing zeolite basicity. H-2 production at 300 degrees C increased in the order of Ni/Cs-Y > Ni/K-Y > Ni/Na-Y, and selectivity for a high production ratio of H-2 to C2H4 was significantly promoted by exchanging Na+ for K+ or Cs+. H-2 production at 500 degrees C was also enhanced by the zeolite basicity; however, degradation of catalytic activity was mainly caused by carbon deposition on the three samples at this temperature. Ni/Cs-Y, with higher H-2 production than Ni/Na-Y, also exhibited higher resistance to carbon deposition. Increase of the zeolite basicity was effective for selective acceleration of the dehydrogenation reaction with ethanol, inhibition of coke deposition, and the promotion of H-2 production. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ijhydene.2011.08.099

Web of Science

researchmap

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  

The aim of this study is to develop a highly efficient and environmentally friendly water treatment technique. Water treatment by photocatalytic zonation over bare WO3 under visible light irradiation (O-3/vis/WO3) system was performed under different experimental conditions using a phenol aqueous solution as model wastewater. The effects of parameters such as the initial phenol concentration, water temperature, and initial solution pH on the total organic carbon (TOC) removal efficiency in the O-3/vis/WO3 system were investigated. The results suggest that the TOC removal process consists of three stages, and the combined effect of photocatalysis and ozonation, which is important for complete TOC removal, became dominant in the third stage. Furthermore, the TOC removal efficiency increased with increasing water temperature in the O-3/vis/WO3 system. (C) 2011 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.119.822

Web of Science

researchmap

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  

W-doped TiO2 nanofibers with various compositions (W/Ti: 2-8%) were fabricated by the electrospinning method from respective precursor solutions containing tungsten(V) pentaethoxide, titanium tetraisopropoxide (TTIP), and polyvinylpyrrolidone (PVP), followed with calcination at 550 degrees C. Morphological and structural characteristics of these nanofibers were studied with SEM, XRD and XPS. W-doping inhibited the crystal growth and anatase-to-rutile transformation of TiO2 nanofibers. W-doped TiO2 nanofiber mats showed good photocatalytic oxidation abilities for acetone. Obvious color change from white to blue of mats during the photocatalysis process can be detected by naked eyes, which provides a good way in detection of pollutants in indoor air, especially for the volatile organic compounds (VOCs). (C) 2011 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2011.06.041

Web of Science

researchmap

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  

A novel inorganic-organic nanoscopic multilayer film consisting of exfoliated MgAl-type layered double hydroxide (LDH) nanosheets and anthryl dendrons [i.e., poly(amidoamine) dendrons with an anthracene chromophore group at the focal point] was fabricated using an electrostatic layer-by-layer (LbL) assembly. UV-vis spectroscopy and X-ray diffraction analysis indicated the successful LbL growth of dendron/LDH multilayer films. Furthermore, fluorescence spectroscopic analysis indicated that the dendrons are present as a monolayer between LDH nanosheets in the film. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matlet.2011.05.004

Web of Science

researchmap

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  

LiBiO(3), NaBiO(3), MgBi(2)O(6), KBiO(3), ZnBi(2)O(6), SrBi(2)O(6), AgBiO(3), BaBi(2)O(6) and PbBi(2)O(6) were synthesized by various processes such as hydrothermal treatment, heating and so on. These materials were examined for their photocatalytic activities in the decolorization of methylene blue and decomposition of phenol under visible light irradiation. For methylene blue decolorization, the presence of KBiO(3) resulted in complete decoloration within 5 min. For phenol decomposition, NaBiO(3) showed the highest activity, while LiBiO(3), SrBi(2)O(6) and BaBi(2)O(6) possessed almost comparable decomposition rates. Their decomposition rates were apparently higher than that by anatase (P25) under UV irradiation. (C) 2011 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jssc.2011.06.004

Web of Science

researchmap

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

Single crystals of a new bismuth vanadate, Bi-3.33(VO4)(2)O-2 was prepared by hydrothermal reaction using a hydrated sodium bismuthate, NaBiO3 center dot nH(2)O as one of the starting compounds. The crystal structure was determined by using single crystal X-ray diffraction data. This compound crystallizes in the triclinic space group P (1) over bar (#2) with a = 7.114(1), b = 7.844(2), c = 9.372(2) angstrom, alpha = 106.090(7), beta = 94.468(7) and gamma = 112.506(8)degrees, Z = 2 and the final R factors are R1 = 0.052 and wR2 = 0.14 for 2085 unique reflections. The crystal structure is composed by four bismuth atoms with the coordination number of 6 or 8 and two VO4 tetrahedra, and one of four bismuth atoms is statistically distributed in the splitting sites with the distance of 0.83 angstrom. This compound exhibited photocatalytic behavior for decomposition of phenol under visible light irradiation and its activity was less than that of monoclinic BiVO4. (C) 2011 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.materresbull.2011.02.009

Web of Science

researchmap

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

The temperature dependence of the hydrogen adsorption properties of nickel-doped mesoporous silica (MCM-41) synthesized by a direct hydrothermal method was investigated by measuring the amount of hydrogen adsorbed at pressures up to 100 kPa at 298, 373, and 473 K. Nickel-doped MCM-41 adsorbed more hydrogen than undoped MCM-41 and metallic nickel at approximate to 298/0, 373/0, and 473 K/0 kPa due to chemical adsorption enhanced by the highly dispersed nickel particles. Chemical adsorption increased with increasing nickel content and adsorption temperature, suggesting the presence of adsorption sites. The nickel doping also brought the spillover effect, which enhances the physical adsorption of hydrogen. The spillover effect was enhanced at high nickel contents and adsorption temperatures. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ijhydene.2011.02.010

Web of Science

researchmap

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  

A series of K2NiF4-type compounds, La2-xPrxNiO4 (x = 0, 0.6, 1.0, 1.4, and 2.0), were synthesized by solid state reaction for use as cathodes in an intermediate-temperature (500-700 degrees C) solid oxide fuel cell (IT-SOFC). La(2-x)Pr(x)Nia(4) (x = 0 and 0.6) crystallize in the Fmmm space group, while La2-xPrxNiO4 (x = 1.0, 1.4, and 2.0) belong to the Bmab space group. The electrical conductivity increased by Pr doping and La2-xPrxNiO4 (x = 0.6, 1.0, and 1.4) exhibited electrical conductivities similar to one another while Pr2NiO4 had the highest. Single test-cells consisting of samarium oxide doped ceria (SDC) as an electrolyte, Ni-SDC cermet as an anode and La2-xPrxNiO4 as a cathode, were fabricated for measurements of cell performance at 500-700 degrees C. Current interruption measurements revealed that the overpotential losses mainly decreased with increasing Pr content. Pr2NiO4 was found to exhibit the best cathode characteristics; maximum lest-cell power densities of 14.1, 45.1, and 104.4 mW/cm(2) were obtained at 500, 600, and 700 degrees C, respectively. (C) 2011 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.119.246

Web of Science

researchmap

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

The catalytic activity for ethanol steam reforming of Na-Y zeolite supporting transition metals was compared with that of zeolite Y encapsulating transition metal cations. It was found that zeolite Y supporting Co or Ni, prepared by the incipient wetness impregnation process, produced mainly hydrogen at 300 degrees C. Acetaldehyde products indicated that hydrogen production was due to the dehydrogenation of ethanol molecules. On the other hand, for zeolite Y encapsulating cations such as Co(2+) or Ni(2+), prepared by an ion exchange process, the reforming reaction resulted in mainly ethylene production, which was considered to be due to the dehydration of ethanol molecules. The results indicate that the presence of cations in zeolite Y has a significant influence on the ethanol reforming reaction. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ijhydene.2010.08.092

Web of Science

researchmap

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  

Photocatalytic water treatment over bare WO3 under visible light irradiation combined with ozonation (O-3/vis/WO3) was investigated using an aqueous phenol solution as model wastewater. The O-3/vis/WO3 treatment exhibited a much higher total organic carbon removal than ozonation alone. Bare WO3 was found to function as an active visible-light-responsive photocatalyst for decomposition of organic compounds in the presence of ozone, which readily reacts with photoexcited electrons in the conduction band of WO3. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cplett.2010.09.086

Web of Science

researchmap

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 PUBLISHING, INC  

Silicon oxide nanowires were successfully synthesized using a low-temperature hydrothermal treatment (200 degrees C) without the use of metallic catalysts. Scanning electron microscopy and transmission electron microscopy (TEM) revealed nanowires having uniform distribution and straight morphology with diameters ranging from 50 to 100 nm and lengths up to ca. 60 mu m. TEM results suggest that the nanowires consist of a crystalline core and an amorphous sheath. The nanowires were produced by hydrothermal treatment based on our original concept of slow structure formation by the dissolution of bulk glass source materials (borosilicate glasses), which can be used to supply a continuous source solution.

DOI： 10.1111/j.1551-2916.2010.03761.x

Web of Science

researchmap

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  

The Ruddlesden-Popper phases, Lan+1NinO3n+1 (n=1, 2, and 3), were synthesized by a solid-state reaction for use as cathodes in an intermediate-temperature (500 degrees-700 degrees C) solid oxide fuel cell. The samples crystallized into an orthorhombic layered perovskite structure. The overall electrical conductivity increased with the increase of n in the intermediate temperature range. Single test-cells, which consisted of samarium-oxide-doped ceria (SDC; Sm0.2Ce0.8Ox) as an electrolyte, Ni-SDC cermet (Ni-SDC) as an anode, and Lan+1NinO3n+1 as a cathode, were fabricated for measurements of cell performance at 500 degrees-700 degrees C. Current interruption measurements revealed that both the ohmic and overpotential losses at 700 degrees C decreased with the increase of n. La4Ni3O10 was found to exhibit the best cathode characteristics in the Lan+1NinO3n+1 series. Maximum test-cell power densities with La4Ni3O10 (n=3) were 10.2, 36.5, and 88.2 mW/cm2 at 500 degrees, 600 degrees, and 700 degrees C, respectively.

DOI： 10.1111/j.1551-2916.2010.03743.x

Web of Science

researchmap

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  

This Letter describes a new fabrication process for superhydrophilic-superhydrophobic patterns on a TiO(2) surface using a combination of an inkjet technique and the site-selective decomposition of a self-assembled monolayer (SAM) by a photocatalytic reaction under UV irradiation. To induce high surface wettability, we carried out simple calcination of a Ti substrate. The substrate was thus oxidized to titanium oxide and had a vortex-like rough morphology, which was suitable for the formation of wettability patterns. Furthermore, the substrate can be regenerated after elimination of the superhydrophilic-superhydrophobic patterns by the photocatalytic decomposition of TiO(2) using UV irradiation, and the patterns are deposited again. The renewed surface that we created had a wettability pattern that was different from the preceding pattern. This process is based on a TiO(2) surface and should offer a renewable, resource-saving, and environmentally friendly methodology for the formation of wettability patterns

DOI： 10.1021/la101947y

Web of Science

researchmap

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  

A novel combination for an inorganic-organic nanocomposite material was demonstrated. Anthryl dendron, i.e., poly(amidoamine) dendron with an anthracene chromophore group at the focal point, was incorporated in the interlayer space of ZnAl-NO(3) type layered double hydroxide (LDH) through an anion-exchange reaction. The photoabsorption and fluorescence properties of the resulting material were different from those of the bare anthryl dendron molecule. It was suggested that the change in photochemical properties was due to the organization and pi-pi interaction of anthracene chromophores within the interlayer of the LDH. (C) 2010 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jssc.2009.12.016

Web of Science

researchmap

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  

This work describes that the photocatalytic activity of microsized TiO2 fibers for degrading gaseous acetaldehyde can be systematically enhanced by introducing nanostructured interior hollow channels, which is achieved by a facile multifluidic electrospinning method. The increased channel number augments the BET surface area of TiO2 fibers intuitively. A quite interesting phenomenon is that the percentage increase for photocatalytic activity is higher than that for surface area. It is thus proposed that the multichannel hollow structures induce not only an inner trap effect on gaseous molecules, but also a multiple-reflection effect on incident light, which further improves the photocatalytic activity of TiO2 hollow fibers.

DOI： 10.1039/c0jm00484g

Web of Science

researchmap

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 PUBLISHING, INC  

Dense b-axis-oriented ZSM-5 zeolite films with a thickness of approximately 300 nm were successfully synthesized on porous Y(2)O(3)-stabilized ZrO(2) supports. The films were produced via an in situ crystallization method based on a slow dissolution of solid source materials, which continuously supplies a superficial layer for the film growth.

DOI： 10.1111/j.1551-2916.2009.03290.x

Web of Science

researchmap

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  

Layered perovskite Ca3Ti2O7 codoped with Rh and Ln (Ca(3-x)Ln(x)Ti(1.9)Rh(0.1)O(7); Ln = La, Pr, Nd, Eu, Gd, Yb, and Y; 0 <= x <= 0.15) was synthesized by a conventional solid-state reaction to investigate the effects of Rh and Lit codoping on the photocatalytic activity. Rh and Ln-codoped Ca3Ti2O7 exhibited a higher photocatalytic activity than Rh-doped Ca3Ti2O7 for H-2 production from an aqueous methanol solution under visible light irradiation (lambda > 420 nm). In addition, the induction period for H-2 production was shortened by codoping with Rh and Ln. The codoped elements helped control the oxidation state of Rh ions and suppressed the formation of oxygen defects, improving the activity of the Rh-doped Ca3Ti2O7 photocatalyst. (C) 2009 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.117.1175

Web of Science

researchmap

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 renewable superhydrophobic-superhydrophilic pattern with a minimum dimension of 50 mu m is prepared from octadecyltrimethoxysilane self-assembled monolayer-covered superhydrophobic Al2O3 overlayers on a superhydrophilic TiO2 surface via self-assembly and calcination of boehmite (AlOOH center dot nH(2)O) particles. The resulting Al2O3 layer plays dual roles as a superhydrophobic layer and as a UV-blocking layer for the underlying TiO2.

DOI： 10.1021/la9011372

Web of Science

researchmap

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  

A photosensitive TiO2 thin film embedded with Ag nanoparticles has been prepared from a Ti(OBu)(4)-acetylacetone solution, containing dispersed Ag nanoparticles, by the sol-gel method. UV-visible absorption spectra showed that the thin film obtained has two absorption bands, characteristic of the acetylacetone chelate rings and plasmon resonance from Ag nanoparticles. After the irradiation of UV light, the absorption band from the chelate rings almost disappeared. ascribed to structural changes associated with dissociation of the chelate rings. The thin film after the UV irradiation exhibited a broad absorption band in the IR spectrum, indicating that a Ti-O-Ti network was formed in the thin film. HRTEM and EDX spectra revealed that Ag nanoparticles were present and dispersed in the TiO2 thin film. Micro-patterns of 50 mu m dots have been fabricated by UV irradiation through a corresponding photomask, followed by leaching. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matlet.2009.04.035

Web of Science

researchmap

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  

A superhydrophobic-superhydrophilic pattern was prepared on an anodized Al plate by a new fabrication process. The process consists of five key steps: (1) TiO2 coating of the plate, (2) surface modi. cation with self-assembled monolayers (SAMs), (3) formation of aqueous UV light-resistant ink patterns by an ink-jet technique, (4) photocatalytic decomposition of SAMs and surface conversion to the superhydrophilic state and (5) removal of the aqueous ink patterns by water washing. It is particularly noteworthy that the wettability pattern can be quickly formed on the plate, without the use of a photomask. The fabricated superhydrophobic-superhydrophilic pattern is shown to be applicable to offset printing. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apsusc.2009.01.084

Web of Science

researchmap

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  

One of the commercial N-doped TiO2 powders (Sumitomo Chemicals, TPS 201) was studied as a model material by photocatalytic and photoelectrochemical methods in order to evaluate the photoactivity of N-doped TiO2 materials and the possibility of their applications in solar photocatalysis. The N-doped TiO2. powder (TPS) was able to degrade and mineralize phenol under solar or visible light (VL) irradiation, and the degradation rate was strongly dependent on the suspension concentration. Photoelectrochemical studies showed that the VL-irradiated TPS electrode was able to oxidize water, phenol, as well as maleic acid, an open-ring oxidized product of phenol, consistent with the results of photocatalytic studies. Calcining the TPS powder at/over 773 K was found to lower the absorption in the VL region and the photocatalytic activity under VL irradiation, but improve the photocatalytic activity under solar irradiation, suggesting that the mid-gap states introduced by nitrogen doping also worked as recombination centers. Deposition of Pt (0.2 wt%) on the TPS photocatalyst thus greatly increased the degradation rate of phenol under either solar or VL irradiation due to the suppression of charge recombination, and the degradation rate was found to be higher than a pristine TiO2 photocatalyst (ST-01, anatase) either with or Without loading of Pt. The potential application of the N-doped TiO2 in solar photocatalysis was discussed on the basis of above-mentioned studies. (c) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jphotochem.2008.11.007

Web of Science

researchmap

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  

A fabrication process for superhydrophilic-superhydrophilic patterns on titanium substrates prepared through a combination of an ink-jet technique and site-selective decomposition of a self-assembled monolayer (SAM) by a TiO2 photocatalyst under UV irradiation is described. We demonstrate that the prepared titanium substrate is applicable as an offset printing plate with high resolution (133 and 150 lines per inch). Furthermore, the superhydrophilic-superhydrophobic patterns on the substrate can be deposited repeatedly after elimination of the patterns by photocatalytic decomposition of TiO2 under UV irradiation. A second printed image with the renewed substrate showed no significant difference in image quality compared with the initial image.

DOI： 10.1002/asia.200900005

Web of Science

researchmap

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  

Particles-stabilized TiO(2) icecream-like foam was prepared by a versatile mechanical stirring method. It showed ultrastable state in air for several days. After calcining the wet foam, an open honeycomb-like structure with macro-/meso-porosity was formed. The photocatalytic characters of as-prepared macro-/meso-porous materials were detected, and the results indicated that the catalytic activity is increased about 120% compared to that of nanoparticles with acetaldehyde as a probe. Composite porous structure provided open pathways for high accessibility of molecular transport, increased surface area for more active center, and enhanced light-collection efficiency due to the inner light scattering effect, resulting in better photocatalytic activity. (C) 2008 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.micromeso.2008.05.024

Web of Science

researchmap

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  

Highly ordered TiO2 nanotube array prepared by electrochemical anodization generates considerable interest as a practical air purifier, since a nanotube array can form a TiO2 film with a porous surface and straight gas diffusion channel, simultaneously reserving enough geometric thickness. Here, we reported on the application of highly ordered TiO2 nanotube arrays with different lengths for degradation of gaseous acetaldehyde pollutants in air. The results showed that increasing the lengths of nanotube arrays within a certain range could significantly improve the degradation rate of acetaldehyde molecules, The main product of acetaldehyde degradation was detected to be CO2, which indicated that the mineralization of acetaldehyde molecules was the major process in this photocatalytic reaction. When compared with a P25 TiO2 nanoparticulate film with similar thickness and geometric area, in the initial degradation of acetaldehyde, the nanotube array did not show obvious superiority. However, in the subsequent degradation, the nanotube array demonstrated an enhanced photocatalytic activity. It was suggested that this enhancement resulted from the special infrastructure of the nanotube array, which was favorable for the diffusion of intermediates and the reduced deactivation of photocatalyst in the photocatalytic reaction.

DOI： 10.1021/es8016842

Web of Science

researchmap

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  

Photocatalytic activity of hierarchically micro-/nano-porous film is studied for the first time. The results show its catalytic activity was increased ca. 30-40% and ca. 60-70% for mineralizing gaseous acetaldehyde and liquid-phase phenol, respectively. comparing to that of nanostructured film. Hierarchical TiO2 porous film produces continuously composite pore channels. providing the fast trans-port pathway for reactants. products and 0, moving into and Out of the catalytic framework. Additionally, due to extended optical path length from light scattering effect in composite film, the light-absorption efficiency is enhanced distinctly in the range of 380-410 nm, which is close to P25 TiO2 band-gap edge. The presented investigation indicates that the pores structure plays important roles in the photocatalytic characters of films photocatalyst. More important, the as-prepared film catalyst gives a promising future for its actual application. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apcatb.2008.01.035

Web of Science

researchmap

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  

A hydrophobic/super-hydrophilic pattern was prepared on a TiO2 thin film by a new fabrication process. The process consists of five key steps: (1) photocatalytic reduction of Ag+ to Ag (nucleation), (2) electroless Cu deposition, (3) oxidation of Cu to CuO, (4) deposition of a self-assembled monolayer (SAM), and (5) photocatalytic decomposition of selected areas of the SAM. A hydrophobic/super-hydrophilic pattern with 500-mu m(2) hydrophilic areas was obtained in this process. It is particularly noteworthy that a UV irradiation time of only 1 s was sufficient for the nucleation step in the patterning process. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apsusc.2008.03.153

Web of Science

researchmap

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  

The photocatalytic activities of layered-perovskite Ca(3)Ti(2)O(7) doped with Rh were investigated with visible light irradiation. Although the Rh-doped Ca(3)Ti(2)O(7) as prepared showed low activity after an induction period, the photocatalytic activity was highly enhanced by treating the samples in reducing atmosphere without the need for an induction period. The rate of H(2) evolution from an aqueous methanol solution by 3 mol% Rh-doped Ca(3)Ti(2)O(7) after the reduction treatment was about 5 times higher than that before the reduction. The layered photocatalytic compounds, Ca(3)Ti(2-x)Rh(x)O(7), showed higher stability in air than CaTi(1-x)Rh(x)O(3), which consists of a simple perovskite structure. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matlet.2008.02.052

Web of Science

researchmap

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  

Highly ordered TiO2 nanotube array prepared by a potentiostatic anodization shows a considerable potential for improving the transport of the photogenerated electrons in the TiO2 film, since the ordered architecture can provide a unidirectional electric channel and reduce the grain boundaries. Here, we report on the application of highly ordered TiO2 nanotube arrays with different lengths for the photoelectrocatalytic degradation of phenol. The lengths of the nanotube arrays can be controlled by the electrolyte media, anodization time, or both. The photoelectrocatalytic activity shows a dependence on the length of the nanotube arrays. Under 3.1 mW/cm(2) irradiance of ultraviolet light, a short nanotube array shows better photoelectrocatalytic activity than a long nanotube array, which can be explained by the reduced recombination effects. When compared with a P25 TiO2 particulate film with similar thickness and geometric area, the nanotube array shows a stronger attachment to the parent titanium substrate and a better photoelectrocatalytic activity for phenol degradation owing to the improved electron transport and reduced charge recombination. This superior electron transport is further supported by the remarkably enhanced anodic photocurrent response in the degradation of phenol.

DOI： 10.1021/jp0772732

Web of Science

researchmap

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  

A transparent superhydrophobic TiO2 film, prepared by spincoating a TiO2 slurry on a glass substrate and modifying the resultant TiO2 film with fluoroalkylsilane molecules, was patterned by illumination with ultraviolet light through a photomask, producing a superhydrophobic/superhydrophilic surface micropattern with very small superhydrophilic areas, which we were able to selectively fill with alginate hydrogel.

DOI： 10.1039/b713432k

Web of Science

researchmap

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 report herein the preparation and UV-stimulated wettability conversion of superhydrophobic TiO2 surfaces, as well as the preparation of superhydrophilic-superhydrophobic patterns by use of UV irradiation through a photomask. A CF4 plasma was used to roughen smooth TiO2 sol-gel films to produce a nanocolumnar morphology, and subsequent hydrophobic modification with octadecylphosphonic acid (ODP) rendered the roughened surfaces superhydrophobic. The superhydrophobic properties of these surfaces were evaluated by both static and dynamic water contact angle (CA) measurements. It was found that the surface morphology of the TiO2 film, which was dependent on the etching time, has a great influence on the observed superhydrophobic properties. The nanocolumnar surface morphology exhibited large water CA and small contact angle hysteresis (CAH); this is discussed in terms of the Wenzel equation and the Cassie-Baxter equation. Under low-intensity UV illumination, (1 mW cm(-2)), the superhydrophobic TiO2 surface underwent a gradual decrease of water CA and finally became superhydrophilic, due to photocatalytic decomposition of the ODP monolayer. Readsorption of ODP molecules led to the recovery of the superhydrophobic state. This UV-stimulated wettability conversion was employed to prepare superhydrophilic stripes (50 and 500 mu m wide) on a superhydrophobic TiO2 surface. The pattern was able to guide water condensation, as well as the evaporation of a polystyrene microsphere suspension, due to the extremely large wettability contrast between superhydrophobic and superhydrophilic areas.

DOI： 10.1021/jp0744432

Web of Science

researchmap

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 report here the use of a layer-by-layer assembly technique to prepare novel TiO2 heterogeneous nanostructures in which anatase nanoparticles are assembled on rutile nanorods. The preparation includes assembling anatase nanoparticle multilayers on rutile nanorods via electrostatic deposition using poly(sodium 4-styrene sulfonate) as a bridging or adhesion layer, followed by burning off the polymeric material via calcination. The composition of the heterogeneous nanostructures (i.e., the anatase-to-rutile ratio) can be tuned conveniently by controlling the experimental conditions of the layer-by-layer assembly. It was found that, with the optimum preparation conditions, the heterogeneous nanostructures showed better photocatalytic activity for decomposing gaseous acetaldehyde than either the original anatase nanoparticles or the rutile nanorods. This is discussed on the basis of the synergistic effect of the existence of both rutile and anatase in the heterogeneous nanostructure.

DOI： 10.1021/la7018023

Web of Science

researchmap

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

Heat treatment of various compositions of AgNO3-doped polyvinylpyrrolidone (PVP) composite nanofibres fabricated by electrospinning produced two kinds of silver species: (i) Ag nanoparticles dispersed in PVP nanofibres, when the loading of AgNO3 was 5 wt%, and (ii) a net-like silver nanofibre film when the loading of AgNO3 was five times greater than that of PVP in the composite nanofibres. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-visible absorption spectroscopy, FT-IR spectra, powder x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) were used to characterize the silver nanoparticles and nanofibres. The formation mechanisms are discussed based on the redox reaction between AgNO3 and PVP during heat treatment; essentially, the weight ratios of AgNO3 to PVP determined the types of morphologies, from Ag nanoparticles to silver nanofibre film. The present results may find some potential application in the design of new composite materials in the dielectric and electronics areas.

DOI： 10.1088/0957-4484/18/7/075605

Web of Science

researchmap

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  

Silver-TiO2 nanofibers (Ag/Ti = 1/50) were fabricated by the electrospinning method, followed by heat treatment at 200 degrees C and calcination at 550 degrees C. The electrospinning solution was comprised of AgNO3 and titanium tetraisopropoxide (TTIP) with polyvinylpyrrolidone (PVP). Alternating irradiation of the silverTiO(2) nanofibers with ultraviolet and visible light can interconvert the silver species on the TiO2-based nanofibers to yield Ag metal and Ag2O, respectively, and this process has been characterized by UV-visible spectra, TEM, XRD, and XPS. The interconversion process can be rationalized in terms of the photoreduction of Ag2O by TiO2 and the oxidization of Ag by visible light. Acetaldehyde photodecomposition measurements indicate that Ag2O has better mineralization ability than Ag-0 in this kind of silver-TiO2 nanofiber photocatalytic system. The photoinduced conversion of composition on TiO2-based nanofibers may find applications in photocatalysis, antibacterial technology, and other areas.

DOI： 10.1021/jp065590n

Web of Science

researchmap

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  

A layered perovskite compound with Na+, D3O+ ions (H3O+) and D2O molecules (H2O) in the interlayer, DxNa1-xLaTiO4 center dot gamma D2O, has been prepared by an ion-exchange/intercalation reaction with dilute DCl solution, using an n = 1 Ruddlesden-Popper phase, NaLaTiO4. Its structure has been analyzed in order to clarify the interlayer structure by Rietveld method, using powder neutron diffraction data. The structure analysis revealed that the layered structure changed from the space group P4/nmm-14/mmm after the ion-exchange/intercalation reaction, and it induced the transformation of perovskite layers from staggered to an eclipsed configuration. The D2O molecules and D3O+ ions loaded in the interlayer statistically occupied the sites around a body center position of rectangular space surrounded by eight apical O atoms of TiO6 octahedra in upper and lower layers. (c) 2006 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jssc.2006.06.019

Web of Science

researchmap

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 present here a facile method for the preparation of TiO2-based superhydrophobic surfaces. It consists of two steps: (1) roughening of the TiO2 surface with a rf (radio frequency) plasma with CF4 as an etchant and (2) modification of the roughened TiO2 surface with an octadodecylphosphonic acid (ODP) monolayer. Plasma etching caused the thinning of the TiO2 film but at the same time enhanced its surface roughness. A discontinuous wedgelike surface microtexture was formed after etching for 30 s, which, after modification with a monolayer of ODP, showed Cassie-type water super-repellency with a contact angle (CA) hysteresis smaller than 2. The state of water super-repellency (water CA > 165 degrees) could be converted to the state of superhydrophilicity (water CA similar to 0 degrees) by means of ultraviolet (UV) illumination as a result of the photocatalytic decomposition of the ODP monolayer by TiO2. Readsorption of ODP molecules leads directly to the recovery of water super-repellency.

DOI： 10.1021/la0618869

Web of Science

researchmap

記述言語：英語   出版者・発行元：ACADEMIC PRESS INC ELSEVIER SCIENCE  

DOI： 10.1016/j.jssc.2006.07.035

Web of Science

researchmap

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  

A deuterated n = 1 Ruddlesclen-Popper compound, DLnTiO(4) (HLnTiO(4), Ln = La, Nd and Y), was prepared by an ion-exchange reaction of Na+ ions in NaLnTiO(4) with D+ ions, and its structure was analyzed by Rietveld method using powder neutron diffraction data. The structure analyses showed that DLaTiO4 and DNdTiO4 crystallized in the space group P4/nmm with a = 3.7232(1) and c = 12.3088(1) angstrom, and a = 3.7039(1) and c = 12.0883(1) angstrom, respectively. On the other hand, DYTiO4 crystallized in the space group P2(1)/c with a = 11.460(1), b = 5.2920(4), c = 5.3628(5) angstrom and beta = 90.441(9)degrees. The loaded protons were found to statistically occupy the sites around an apical oxygen of TiO6 octahedron in the interlayer of these compounds, rather than Na atom sites in NaLnTiO(4). (c) 2006 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jssc.2006.03.015

Web of Science

researchmap

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

Hydrous protonated forms of layered perovskite titanotantalate were derived from the n=3 Dion-Jacobson-type RbLa2Ti2TaO10 by ion-exchange of the interlayer Rb+ ions in aqueous HNO3, and their interlayer reactivity with n-alkylamine was investigated. Although all of the protonated forms thus derived were indexed as the same tetragonal cell with P4/mmm as the host, the interlayer reactivity with n-alkylamine was degraded with an increase in the ion-exchange treatment time. A significant difference was observed in dehydration behavior below 200 degrees C. The protonated forms synthesized with short ion-exchange time showed a large endothermic peak with weight loss around 60 degrees C, while those with prolonged treatment time did not. The intercalation of n-alkylamine was confirmed for the former, but not for the latter. From these results, it was considered that hydronium ions and/or H2O Molecules responsible for the dehydration around 60 degrees C play an important role in the intercalation of n-alkylamine into the protonated forms. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jpcs.2006.01.065

Web of Science

researchmap

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  

The effect of cation substitution into CaTiO3 has been investigated. Rh-doped CaTiO3 showed intense absorption in the visible light region (lambda > 420 nm), and was found to be a new photocatalyst for H-2 evolution from ail aqueous methanol Solution under visible light irradiation.

Web of Science

researchmap

A protonated n = 1 Ruddlesden-Popper compound, HLaTiO4 (DLaTiO4), has been prepared by an ion-exchange reaction of Na+ ions in NaLaTiO4 with H+ (D+) ions, and its structure has been analyzed in order to clarify the location of protons in the interlayer space, using powder neutron diffraction data. The crystal structure of DLaTiO4 belongs to the same space group, P4/nmm, as that of parent NaLaTiO4, and the D atoms were found to statistically occupy eight equivalent sites around an apical O atom of a TiO6 octahedron in the interlayer, which are different from the Na atom sites in NaLaTiO4. A comparison between DLaTiO4 and NaLaTiO4 indicated that the protonation brought the shrinkage of the interlayer space and the distortion of the TiO6 octahedron. © 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jeurceramsoc.2005.07.001

Scopus

researchmap

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  

New derivatives of layered perovskite compounds with H3O+ ions, W ions and water molecules in the interlayer, HxNa1-xLaTiO4 (.) yH(2)O, were successfully synthesized by an ion-exchange/intercalation reaction with dilute HCl solution, using an n = 1 member of Ruddlesden-Popper phase, NaLaTiO4. Powder X-ray diffraction revealed that the layered structure changed from space group P4/nmm with a = 3.776(1) and c = 13.028(5) angstrom to I4/mmm with a = 3.7533(3) and c = 28.103(4) angstrom after the ionexchange/intercalation reaction at pH 5. The change of space group indicates that the perovskite layers are transformed from staggered to an eclipsed configuration through the ion-exchange/intercalation reaction. Thermogravimetric analysis and high-temperature powder X-ray diffraction suggested the existence of the secondary hydrated phase by dehydrating HxNa1-xLaTiO4 (.) yH(2)O at 100 degrees C. (c) 2005 Elsevier Inc. All rights reserved.

Web of Science

researchmap

researchmap

記述言語：日本語   出版者・発行元：無機マテリアル学会  

CiNii Article

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：日本セラミックス協会  

CiNii Article

CiNii Books

researchmap