The surface modification by ammonium molybdate was conducted on the aluminium supported platinum catalysts. The NOx purification activity by using hydrogen as a reducer (H2-SCR) was well improved by such surface modification to show 70% of N2 conversion. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) revealed that ammonia intermediate species generated during the reaction stably adsorbed at Brønsted acid sites generated by the surface modification. The present H2-SCR for NOx proceeds like NH3-SCR, resulting in the high N2 selectivity.

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Water-retentive porous ceramics were made from mixed powder of fly ash (or wollastonite), pearlite, blast-furnace slag. In this work, aging variations of surface temperature and water amount were investigated for affirming the latent heat of evaporation. As a conclusion, our research revealed this porous ceramics can be useful for relaxing the heat island effect by the continuous constant drying, which keeps surface temperature low.

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Titanium salt solution was impregnated into organic monolith particles and porous TiO₂ sphere particles were prepared by subsequent calcination. The pore size in the TiO₂ spheres were around 20 nm, and its distribution was narrow. The surface of the spheres were modified by Tungsto(VI) phosphoric acid and octadecylphosphonic acid. The photocatalytic decomposition activity of 1,4-dioxane in aqueous solution was improved by these treatments. The effect of these surface modifications were discussed.

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Fundamental aspect of sonophotocatalytic reaction with photocatalytic fiber was surveyed. Photocatalytic fiber has advantages that separation from liquid phase is easier than photocatalytic particles. Frequency of ultrasound generator used was 200kHz or 2.4MHz. A KI aqueous solution was employed to evaluate sono/photocatalytic oxidation. In the result, simultaneous irradiation of ultrasound at 2.4MHz and ultraviolet to photocatalytic fiber demonstrated synergetic effect. This specific phenomenon is because microjet effect occurred by 2.4MHz ultrasound irradiation, and then photocatalytic activity increased. Sonochemical field in the presence of fibers were visualized by a luminol method.

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Gaseous ammonia has a characteristic pungent odor and its high concentration gas is harmful for human health. For the removal of ammonia from indoor air, its photocatalytic decomposition is expected to be effective. In this work, the composite photocatalysts which consist of TiO₂ and tungstphosphoric acid as a solid acid were prepared and their adsorption and photocatalytic decomposition properties against gaseous ammonia were investigated. The composite exhibited 3.5 times of ammonia adsorption capacity larger than that of TiO₂. The decomposition rate of ammonia by the composite was almost the same of that of TiO₂ however the amount of ammonia on the composites were largely decreased.

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SiO2-TiO2 sol / montmorillonite (Mont) composites were prepared by mixing of Mont suspension with tetraethoxysilane and titanium tetra-n-butoxide solution. Obtained samples were characterized by XRD, EDS analysis and N2 adsorption-desorption. Degradation behavior of bisphenol A (BPA) under visible light was measured by HPLC and TOC analysis. Commercial TiO2 (P25) was used for reference sample. The obtained sample showed a similar degradation behavior of BPA to reference TiO2 though the TiO2 content was different. However, the generation behavior of the intermediate product was different between the obtained sample and commercial TiO2.

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By the surface treatment of crystallized TiO2 particle used hydrogen peroxide and sulfuric acid in an aqueous suspension and heat treatment improve the photocatalytic activity of crystallized TiO2 particles was improved compared with that of untreated crystallized TiO2 particles. The effect of surface treatment on photocatalytic behavior of rutile TiO2 particles was much higher than that of anatase TiO2 particles.

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Photocatalytic properties of compounds containing Cu⁺ ions are interesting since their visible light responses owing to the contribution of the Cu3d orbital to the valence bands are expected. In the present research, the synthesis of Cu_3xLa_1-xTa₇O₁₉ solid solutions and the evaluation of their photocatalytic properties were carried out. Cu_3xLa_1-xTa₇O₁₉ solid solutions except for x=0 showed intense absorption in the visible light region. The Cu_3xLa_1-xTa₇O₁₉ solid solutions showed photocatalytic activities for H2 and O2 evolution in the presence of sacrificial reagents, methanol and silver ions, respectively. Thus, it has been found that the Cu_3xLa_1-xTa₇O₁₉ solid solutions function as visible-light-driven photocatalysts.

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Rutile TiO₂ particle was prepared from HNO₃ treated BaTiO₃. The specific surface area and crystallite size of rutile TiO₂ were altered by changing dry temperature of rutile TiO₂ sol. The visible light sensitive photocatalysts were obtained by grafting Cu ions onto the surface of the prepared rutile TiO₂ and their photocatalytic activity was evaluated using 2-propanol decomposition. Decomposition activity was the highest when the Cu concentration was about 0.1 mass%.

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Performance of anode supported SOFCs using apatite-type lanthanum silicate films were studied in relation to the structure and fabrication conditions. The electrolyte films were deposited by an atmospheric DC plasma spraying method. Power generation performances were changed with thickness and dopants of the electrolyte films, plasma gases and input powers, thickness and compositions of the anode substrates.

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The electrochemical performance of three-dimensionally ordered macroporous (3DOM) anode-supported SOFC was investigated by feeding 13A gas. At 700 ° C, the cell with 3DOM anode (3DOM-type) showed 1.3 times higher power density than that with random-structured anode (conventional-type). Furthermore, the polarization resistance of 3DOM-type cell was low compared with the conventional-type cell at low current densities. This result suggests that reforming reactions of 13A gas were promoted in 3DOM anode.

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Gd₂O₃ doped CeO₂ thin films were deposited on SiO₂/Si(001) substrates by chemical vapor deposition, using Ce(EtCp)₃ and Gd(EtCp)₃ as precursors. The (001) uniaxial oriented GDC film was obtained at lower temperature and lower deposition rate. The polycrystalline films were deposited at higher temperature and higher deposition rate. It is clear the uniaxial film showed higher film density and higher electrical conductivity and lower activation energy.

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We have successfully synthesized the highly c-axis-oriented polycrystals of apatite-type lanthanum silicate by the reactive diffusion technique. When the sandwich-type La2Si2O7/La2SiO5/La2Si2O7 diffusion couples were isothermally heated at 1873 K for 100 h, the apatite polycrystals readily produced in the form of layer at the interfacial boundaries. The annealed couple was mechanically processed and the thin-plate electrolyte consisting of the highly c-axis-oriented polycrystal was obtained. The oxide-ion conductivity was determined from the impedance spectroscopy data at 573 K - 973 K, which steadily increased from 2.4 × 10-3 Scm-1 to 2.4 × 10-2 Scm-1 with increasing temperature. The empirical activation energy of conduction was 0.35 eV, which compares well with the calculated migration energy of 0.32 eV in a previous study.

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Thin films of garnet-type Li₇La₃Zr₂O₁₂ (LLZ) were prepared for the application of all-solid-state thin film lithium batteries. Thin films were prepared by a dip-coating process using a precursor sol from Zr-alkoxide and Li and La nitrates. The thin film of polycrystalline cubic LLZ with a thickness of about 800 nm was obtained after sintering at 900 degree with Li₂CO₃ powder.

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The compatibility of Li7La3Zr2O12 (LLZ) with conventional cathode materials was investigated for development of all-solid-state rechargeable batteries using lithium-metal anode. From XRD analyses on the mixtures of LLZ and cathode materials before and after the heat treatment at 700 °C, it was inferred that Co-based cathode materials such as LiCoO2 and LiNi1/3Co1/3Mn1/3O2 are applicable to LLZ by a simple solid-state process.

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Aerosol Deposition (AD) technique has been used in fabrication of an all-solid-state Li-ion battery. AD thick film single layer investigations revealed that the materials used are dense and have an acceptable ionic conductivity. Stable 3-layered structures using Li₄Ti₅O₁₂, Li_1.3Al_0.3Ti_1.7(PO₄)₅ and LiCoO₂ as anode, electrolyte and cathode materials were successfully fabricated at room temperature using AD technique. Moreover, these structures showed battery behavior, being possible to charge and discharge these structures.

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The grain boundary structure of LiCoO2 thin films has been studied by a combination of atomic scale HAADF-STEM observations and first-principles calculations.

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The structure and properties of domain boundaries in epitaxial thin films of rhombohedral LiCoO₂ deposited on sapphire substrates are reported, based on a combination of atomic-level simulation and high-angle annular dark field scanning transmission electron microscopy. The results show that the domain boundaries are of an inverse antiphase type, and their high excess energies indicate they are not particularly stable. Examination of the film/substrate interface reveals that the domains form because steps on the nominally flat substrate displace one LiCoO₂ domain relative to its neighbors by one cation layer spacing.

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Ionic configurations and total energies of ordered-spinel LiNi_0.5Mn_1.5O₄ were systematically computed by first principles calculation. Our calculations reveal that a ferrimagnetic P4₃32 structure is the most stable state. Electronic structures of the P4₃32 phase were investigated. The redox reaction ofLiNi_0.5Mn_1.5O₄ is attributed to changes in valence states of Ni ions. Valence states of Mn ions make less contribution. We evaluated theoretical voltages of hypothetical spinel compound such as LiNi_0.5Ti_1.5O₄. Our calculations reveal that they also have theoretical voltages of about 5V.

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Structural and magnetic properties of both electrochemically (EC-) and chemically (C-) delithiated LixNiO2 samples have been studied by powder X-ray diffraction, magnetic susceptibility (\chi), and muon-spin rotation and relaxation (\muSR) measurements. Zero-field \muSR spectra for the C-Li0.01NiO2 sample exhibit a large relaxation compared with these for EC-Li0.1NiO2, indicating the presence of H+ ions in the C-Li0.01NiO2 lattice. Based on the effective magnetic moment of the Ni ions, the composition of the C-Li0.01NiO2 sample is estimated to be H~0.5Li0.01NiO2.

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The effect of surfactants on hydrothermal synthesis of LiCoPO4 was investigated in order to obtain small particles with high crystallinity. When the pH value of precursor solution was 5, cubic LiCoPO4 particles were obtained regardless of addition of carboxymethylcellulose (CMC) after the hydrothermal treatment at 200 °C for 24 h. However, the size of particle that obtained from the precursor solution with CMC was much smaller than that obtained without CMC. This result suggests that addition of surfactant to the precursor solution is effective to control the particle morphology of resulting LiCoPO4.

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