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The crystal structure of Ag2GeO3 was determined from laboratory X-ray powder diffraction data (CuKα1) using the Rietveld method. The title compound is orthorhombic with space group P212121, Z = 4, unit-cell dimensions a = 0.46309(1) nm, b = 0.71393(2) nm, c = 1.04079(3) nm and V = 0.34410(2) nm3. The final reliability indices were Rwp = 5.58 %, S = 1.26, Rp = 4.20 %, RB = 0.67 % and RF = 0.35 %. The GeO4 tetrahedra form infinite chains of [Ge2O6] along the a axis, with two tetrahedra per identity period of 0.463 nm. Individual chains are connected by Ag atoms, one-half of which are almost linearly coordinated by two O atoms, and the rest are coordinated by three O atoms. The relatively short Ag-Ag distances of 0.299 - 0.339 nm indicate Ag(I)-Ag(I) interaction. This compound is isostructural with Ag2SiO3

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Joint part of silicon nitride was examined by X-ray CT. Crack, inclusion, separation, etc. were successfully observed. X-ray CT is useful as a non-destructive evaluation technique.

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In this research, iron contained nitrogen doped titania was synthesized by hydrothermal method. The influence of the synthesis method on the structure, property and photocatalytic activity of the samples were studied.

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The advances in photocatalysis based on the coupling of nitrogen-doped titania (TiO2-xNy) with CaAl2O4:(Eu, Nd) long afterglow phosphor was investigated. CaAl2O4:(Eu,Nd)/TiO2-xNy composite sample showed persistent catalytic ability even in the darkness after turning off the light for about 3 h while the photocatalytic activity of simplex TiO2-xNy immediately disappeared after turning off the light.

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We have tried to synthesize brookite particles by self-hydrolysis of TiOCl₂ with HCl addition. When 0.1M TiOCl₂ with addition of 2M HCl was heated at 100°C for 24h by reflux method, brookite and rutole formed and the morphology was the agglutinated particle. on the other hand, when 0.075M TiOCl₂ solution with addition of 2M HCl was heated at 100°C for 24h by using autoclave, particles of rutile and brookite formed and the morphology was the particle with a size of 4μm and the dispersed particle with a size of 100nm, respectively. The synthesized particles by using autoclave was separated to rutile and brookite because the brookite had high dispersibility.

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In this study, BaTiO₃ thin films were prepared by CSD method. We designed the molecular structure of the precursor solutions. When Ti precursor solution was prepared, acetic acid was added to the solution for chelating, and then, distilled water was added for the partial hydrolysis. The BT thin films prepared from the partially hydrolysed precursor solution showed better crystallinity and dielectric properties.

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Nanometer sized gold fine particles show a particular optical absorption due to their localized surface plasmon resonance (LSPR). The change of LSPR is sensitive to refractive index around the surface of the particles. Thus, the applications of LSPR owing to the particles have received a lot of attention as a chemical-biosensor. In order to fabricate a LSPR sensor, silica gel thin films loading gold fine particles were prepared by a sol-gel and a dip-coating method and subsequent thermal-reduction process. The sample exhibited the particular optical absorption due to the LSPR. Additionally, the wavelength of the LSPR peak showed red shift against the refractive indices of the examined liquid substances.

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TEMPO oxidized cellulose nanofiber (TOCN)-silica hybrid laminate coating films were prepared via sol-gel method. Those films were characterized by UV-vis transmittance, pencil hardness test, and oxygen permeability determination. Those films had high oxygen-barrier properties and optical transparency almost some as TOCN films. Moreover, those films had good water resistance.

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Zn(OH)2/ZnO nanosheet-ZnO nanoarray hybrid structured films were fabricated on F-doped SnO2-coated glass by a dissolution-recrystallization route without any additives. As-deposited c-axis oriented ZnO nanowhisker films were soaked in hot distilled water for various periods of time. X-ray diffraction, field emission scanning electron microscope and transmission electron microscopy clarified that the dissolution of ZnO induced the growth of Zn(OH)2 at the surface of the ZnO nanowhiskers film by heterogeneous nucleation and growth. The morphology of the Zn(OH)2 nanosheets was found to be controllable by the dissolution-recrystallization of as-deposited ZnO nanowhiskers in hot distilled water. ZnO with almost identical morphology could also be produced by a dehydration reaction. Given the highly porous nature and the strong adsorption properties of the as-fabricated hybrid structured films, it is expected that they will have a variety of potential applications including dye-sensitized gas sensors and solar cells, and photocatalysis systems.

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Several kinds of cubic rare earth oxides such as CeO2, Y2O3, Er2O3, Ho2O3 and Dy2O3 with plate-like morphology were successfully prepared by a simple solution reaction followed by calcination treatment. Plate-like particles of precursor compounds were precipitated at first by the mild solution process using different rare earth salts and precipitation reagents such as ammonia, urea, potassium hydroxide and sodium carbonate etc. The physical and chemical properties of the plate-like oxide particles were characterized in details.

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BaTi2O5 (BT2) films were prepared on Pt/Ti/SiO2/Si substrates by laser CVD using Ba(DPM)2 and Ti(OiPr)2(DPM)2 as precursors. The BT2 films in a single phase were obtained at laser power (PL) between 57 and 112 W, and the deposition temperatures (Tdep) between 908 and 1041 K. The films deposited at 75-79 W (Tdep = 959-970 K) showed the (020) preferred orientation. The (020)-oriented BT2 films consisted of columnar grains with a pyramidal facet, and the grain size increased with increasing PL.

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Stable water-based barium-titanate solution was developed by adjusting the pH of mixed solution of barium acetate and ammonium citratoperoxotitanate. Using the stable solution for dip-coating, uniform and transparent BaTiO₃ thin films were prepared on quartz substrates. The formation of a single phase BaTiO₃ was confirmed by XRD.

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Electrophoretic deposition (EPD) method was applied to deposit thin dielectric film. Fine Ba_xSr_1-xTiO₃ (BST) powder with diameter of about 20 nm slurry was suspended in acetone and iodine was added to obtain EPD suspensions. Zeta-potential of EPD suspensions was increased and particle size was decreased by addition of iodine. H¹ NMR spectra of EPD suspensions also supported increasing zeta-potential by addition of iodine. The effect of iodine was investigated by depositing with DC and pulsed DC source. It found that it was easy to deposit BST powder by using EPD suspensions with iodine to give dense thin films with thickness less than 1 µm.

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Barium titanate (BaTiO3) powders used as raw material were prepared by hydrothermal process. Gd-Mn codoped BaTiO3 powders were pressed and fired at 1380 deg. C in air or in H2-Ar gas. Room temperature resistivity of the sample fired in H2-Ar gas was lower than 10 ohm cm but the positive temperature coefficient of resistivity (PTCR) jump was lower than 1 order magnitude. On the other hand, pronounced PTCR jump (more than 2 order magnitude) was exhibited for the sample fired in air.

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Nitrogen-isotopic heterostructural thin films were deposited by means of a molecular beam epitaxy method. Two radical nitrogen guns were used as sources of nitrogen isotope. The nitrogen isotope abundances were analyzed with a secondary ion mass spectrometry. The thin films were diffusion annealed in nitrogen gas or vacuum. The level of nitrogen diffusivity was two orders of magnitude less than oxygen diffusivity in alumina.

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Defect structures in heavily doped Zinc oxide (ZnO) was investigated by deep level transient spectroscopy (DLTS) and x-ray photoelectron spectroscopy (XPS). Presence of oxygen vacancy, causing deep donor level at 0.3eV, was indicated by DLTS and XPS. These results were consistent to our previous study on oxygen diffusivity in doped ZnO.

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