The relationship between grain size and machining induced damage was investigated for alumina ceramics. Machining induced damage was identified using a fluorescence dye impregnation method with confocal scanning laser fluorescent microscope (CSLFM). Strength degradation is significant for ground specimens with small grains. This strength degradation was understood by observation of fracture surface using CSLFM.

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Nd. YAG fundamental or second harmonic generation laser was applied onto an iron plate through 8-16μm diamond grains placed on the plate. Fundamental YAG laser could achieve more diamonds fixed on the plate with the irradiation than second harmonic. It was found that the number of diamonds fixed on a plate generally increased with laser flux density and irradiation period. AES analysis indicated the existence of carbides on the surface of a plate with laser treatment, which mentions that the diffusion of carbon causes upon the bonding of diamond and iron.

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Layered manganese oxide H-birnessite was exfoliated into a nano-sheet sol solution by reaction with (CH₃)₄NOH solution. A Ni(NO₃)₂ solution was added into the nano-sheet sol solution, then the nano-sheet restack with accommodation of Ni(OH)₂ into the interlayer space, causing formation of a MnO₂-Ni(OH)₂ co-precipitate. After hydrothermal treatment of the co-precipitate, a MnO₂-Ni(OH)₂ sandwich layered compound was obtained. A hexagonal layered Li-Ni-Mn-O phase was prepared by hydrothermal treatment of the sandwich compound in a LiOH solution, and its electrochemical properties was investigated.

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In order to investigate ionic conductivity in olivine-type LiMPO₄, migration energies of Li-ion in LiMPO₄ (M=Mn, Fe, Co and Ni) were calculated using the plain-wave basis pseudopotential method. The migration energy in LiFePO₄ was calculated to be 0.028 eV. This value is as small as that in Li₃N that is well known as the good Li-ion conductor. Other LiMPO₄ also exhibits small migration energy. The small migration energies may be ascribed to the olivine-type structure.

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We have succeeded to disperse well fine carbon particles in Phospho-olivine LiFe_1-xMn_xPO₄ by a solid-state reaction in an Ar atmosphere. The grain growth has been depressed and Fe²⁺/Fe³⁺ ratio in LiFe_1-xMn_xPO₄ decreased by adding carbon particles. LiFe_1-xMn_xPO₄ containing fine carbon showed relatively large capacity and excellent electrochemical properties even at higher current density.

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The initial charge/discharge behavior of LiNi_0.5Mn_0.5O₂ has been examined by XRD, in-situ XAFS and electrochemical methods. The LiNi_0.5Mn_0.5O₂ (a=2.8999(7), c=14.330(7)Å in hexagonal setting) was observed to keep its initial structure after charging up to 4.5V. XAFS analysis revealed that the majority of Ni and Mn exist in a divalent and tetravalent state respectively. Upon charging LiNi_0.5Mn_0.5O₂, Ni⁺ ions were consequently oxidized to Ni⁴⁺.

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By using X-ray micro-beam with 1μm, Ni and Co K-edge XANES spectra at local area of LiNi_0.8Co_0.2O₂ were observed, and the valence change of Ni was obtained. The chemical shift of Ni K-edge energy indicates the change of Ni valence accompanied by charging. Comparing between the XANES spectra at any points in the same grain, no apparent difference was found. It was concluded that the property changes during charge-discharge cycling is independent on the position in the grain.

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The local atomic structures of Ni and Co in LiNi_0.8Co_0.2O₂ during the first charge and discharge were examined by in-situ XAFS measurement on Li//LiNi_0.8Co_0.2O₂ coin cell at room temperature and 60°C. The XAFS analysis suggests that the change of Co-O interaction during charge and discharge at 60°C is associated with the degradation of the performance for battery.

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Electrochemical properties of the mixture of Cu₂S and sulfur were investigated as positive electrode materials for all-solid-state lithium batteries. The all-solid-state lithium batteries were constructed with a-60Li₂S·40SiS₂(mol%) as solid electrolyte and Li_4.4Ge metastable phase as negative electrode materials. The mixture of Cu₂S and sulfur showed a large discharge capacity of 411 mAhg^-1 as a positive electrode materials. This capacity was larger than the theoretical capacity of Cu₂S. The results indicated that not only the Cu₂S but also the sulfur worked as positive electrode materials for all-solid-state lithium batteries.

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Meta-stable alloys Li_4.4Ge_XSi_1-X (0≤X≤1) were prepared by high-energy ball milling process. The electrochemical properties of the obtained Li_4.4Ge_XSi_1-X alloys were investigated as anode materials for all-solid-state lithium batteries. The cells were fabricated with TiS₂ as positive electrode and with a-60Li₂S·40SiS₂(mol%) as solid electrolytes. The cells were charged and discharged under 64μAcm^-2. The Li_4.4Ge_XSi_1-X alloys showed the electrochemical capacities in the range of 700-420mAhg^-1 at room temperature.

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Lithium-ion-conducting amorphous materials 75[(1-x)Li₂O·xLi₂S]·25P₂S₅ (mol%) were prepared by a high-energy ball-milling method. The amorphous materials were obtained over the wide composition range of x=0 to x=1.0. The obtained amorphous materials showed high lithium ion conductivities in the range of 10^-5 to 10^-3Scm^-1 at 25°C depending on their composition. The sample with x=0.9 showed the highest conductivity, 2.7×10^-4Scm^-1, at 25°C. The enhancement of the ion conductivity was probably caused by an anion mixed effect of oxygen and sulfur anions.

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Titanium oxide colloids with different crystallite size of 6-44 nm were prepared by hydrothermal treatment of titanium oxide slurry. Hydrothermal conditions such as the solution pH, liquid-solid ratio, reaction temperature and reaction time significantly affected the crystal growth. The obtained colloids were applied for the semiconductor film electrode of dye-sensitized solar cell. When the crystallite size was around 25-30 nm in diameter, the films showed high energy conversion efficiency about 3.9 % in spite of low temperature sintering at 150°C.

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Titania nano tube was obtained by hydrothermal treatment of nano size TiO₂ fine powder in 10 mol/kg-H₂O NaOH solution for 20h at 110°C. The morphology of product was about 8 nm in diameter and about 100 nm in length with tubular shape. Photovoltaic properties of the titania film using this titania nano tube were examined. The results were V_OC = 0.704 V, I_SC = 1.26 mA, h = 2.9 %, FF = 0.66 for titania nano tube, and V_OC = 0.767 V, I_SC = 1.20 mA, h = 3.0 %, FF = 0.72 for titania nano powder (P-25).

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A low-temperature synthes is route of porous TiO₂ electrodes for dye-sensitized solar cells was investigated. We prepared the electrodes through a low-temperature sintering process of fine TiO₂ particles and subsequent growth of crystalline TiO₂ in an aqueous solution of TiF₄. The maximum conversion efficiency of the solar cells prepared below 100°C was 1.1%.

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Solid acid sulfates such as CsHSO₄ belong to a small class of compounds that exhibit superprotonic phase transitions at relatively low temperatures about 145°C. Thermally stable polymer as GPTS(3-Glycidoxypropyltrimethoxysilane) have good mechanical properties and employed as a matrix for the high proton conductivity inorganic phase. The CsHSO₄-GPTS composites were evaluated in terms of thermal and electrical properties.

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Solid solutions La1-xAxMnO3+d(A= Ca, Sr; 0≤x≤0.5) were prepared and characterized by powder X-ray diffraction method. The local structures around La, Sr and Mn were analyzed by XAFS spectroscopy using the industrial consortium beamline station (BL16) in SPring-8.

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Li_(2-x/3)Cr_xTi_(3-2x/3)O₇(0≤ x ≤ 1.5), with ramsdellite related structure, was synthesized, and its electrode properties were investigated. Its charge-discharge curves had potential plateaus at ca. 4.0V and 1.5V vs. Li/Li⁺. Its parent compound, Li₂Ti₃O₇, showed Ti³⁺/Ti⁴⁺ redox reaction was at 1.5V, and thus the plateau at 4.0V was attributable to Cr³⁺/Cr⁴⁺ redox. Since ramsdellite related structure was the stable three-dimensional structure, lithium ions were extracted and inserted reversibly.

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Hydrothermal oxidation of metal process has advantages to avoid unpleasant influence of anions caused by raw materials and/or to enable controlling size and morphology of particles. In this study, hydrothermal oxidation of Bi metal in KOH and NaOH solutions at 150∼250°C was investigated. The bismuth titanates such as Bi₁₂TiO₂₀ and A_0.5Bi_0.5TiO₃ (A=Na, K) were obtained successfully by hydrothermal oxidation of a mixture of Bi and Ti metal powders.

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Single crystals of Li-Nb double alkoxide were synthesized from a solution of Li ethoxide and Nb ethoxide in Ar atmosphere. Empirical formura of this single crystal was C₂₀H₅₂Li₂Nb₂O₁₂. Single crystals of Li-Nb double alkoxide were converted at low temperatures below 300°C to form LiNbO₃ nano particles. The crystallinity increased with increasing heating temperature. The well-crystallized hexagonal phase was obtained by heating at temperatures over 500°C. The mean particle size of LiNbO₃ heated at 500°C for 1.5h was 33nm.

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Synthesis of single crystal of Ba-Nb mixed alkoxide has been attempted in this study. Single crystal of Ba-Nb mixed alkoxide was successfully synthesized by a reaction of Ba(OEt)₂ and Nb(OEt) ₅ in ethanol. The obtained single crystals were converted into barium niobate by heat treatment. While the as-prepared product was amorphous, the crystallinity of the product increased with an increase in heating temperature and well crystallized hexagonal Ba₅Nb₄O₁₅ was obtained at 800°C. The lattice parameters of Ba₅Nb₄O₁₅ heated at 800°C for 1.5h in air were a=5.79Å, c=11.75Å. The crystallite sizes were 40∼90nm.

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Ba_xSr_1-xTiO₃ nanoparticles were synthesized with sol-gel method using alkoxide complex, ethanol/benzene co-solvent and water (hydrolysis initiator). The titanate particles were characterized with XRD, TEM, IR and XPS. The particles were crystallized above a water concentration of 2 M. Above the water concentration, grain and particle sizes increased from 10 nm to 90 nm with increasing water and benzene concentrations in concentration ranges of 2 ∼ 20 M water and 0 ∼ 5 M benzene. These results can probably be explained by hydrophilicity of hydroxyl groups on the particle surface.

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Ferroelectric lead zirconate titanate (PZT) thin films seeded with barium strontium titanate (BST) crystalline nanoparticles were prepared by the complex alkoxide precursor method on Pt electrode. Their crystallization temperatures were 100°C lower than those of non-seeded PZT films. The crystalline nuclei of the BST particles surface promoted the phase transformation of PZT films into perovskite. The dielectric constants were 100 - 500 for the 25.1mol% BST nanoparticles-seeded PZT films annealed at 420 - 600°C for 1h in air.

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Active gas condensation method combined with a co-evaporation process and uneven bar system is employed to synthesize the ceria-zirconia solid solution based nanocluster composites. The grain size, shapes and composition of the nanocluster composites were controlled by the gas pressure, heating temperature and configuration of the heating boats inside the active gas condensation chamber. High-resolution TEM, SEM and catalytic measurements have been used to characterize the samples and study the synergistic effect between the catalyst phase and the ceria-zirconia solid solution.

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The influence of pre-procedure for starting powder to the microstructure and the deposition rate of the layer prepared by aerosol deposition method was investigated. In this method, high dense layers could be fabricated at normal temperature. Milling procedure decreased density of the layer, but heat treatment was effective to recover the density. The deposition properties were greatly influenced by starting powder properties.

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PZT-Al2O3 nano composite layer prepared by aerosol deposition method was reported. Dry-milling and aerosol mixing procedure were introduced for fabrication of the composite structure. Plastically deformation of PZT particles in deposited layer was observed. Mechanical and electrical properties were changed in proportion to mixing ratio between PZT and α-Al2O3.

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Coating of nickel/alumina composite layer by Aerosol Deposition Method was investigated. Nickel/alumina ratio was controlled by initial amount of nickel and milling time. By scanning electron microscopy, microstructure of the composite layer was observed. Nickel phase was distributed homogeneously in alumina phase. Moreover, we discussed the effect of nickel/alumina ratio on the mechanical and electrical properties of the composite layer.

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An Aluminum oxide (α-Al₂O₃) thin layer was produced using aerosol deposition method. The mechanical properties of the deposited Aluminum oxide on several substrate were determined by hardness tester, contact strength tester and friction tester. We found that the ceramics tribo-coating using this Method was an effective coating technique on the durability of Magnetic Head for Card Reader by friction-testing machine.

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The aerosol deposition method is one of a good fabrication method for ceramics layers, which is on the order of μm. In order to put to practical use electrostatic chucks, an α-Al₂O₃ layer was produced by the Aerosol Deposition Method. The produced layer has excellent property. Therefore we considered that the layer produced by this method was the good material as a electrostatic chucks.

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The influence of substrates heating to microstructure of the layer prepared by aerosol deposition method was investigated. In this method, high dense layers could be fabricated at normal temperature. Heating substrates decreased density of the layer, and no layers were fabricated at 700°C, which were unique phenomenon, compared with other conventional methods.

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Effect of UV irradiation on the gel films prepared by a spin-coating method using aqueous titanate colloidal solutions was investigated. The transparent sols used in this study were prepared from a reaction of titanium isopropoxide (TIP) with tetramethylammonium hydroxide or alkylamines, and consisted of a layered compound. It was found that alkylammonium ions between the layered titanate could be decomposed by photoirradiation to lead to the decrease of the interlayer distance, hardening and densification of the films.

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Thin films of potassium tantalate have been prepared on Ta metal substrates in KOH solutions by the hydrothermal and the hydrothermal-electrochemical methods. Phase-pure perovskite-type KTaO₃ thin films could be formed in 2.0 M KOH at 300°C. Pyrochlore-type K₂Ta₂O₆ thin films were formed at lower temperatures and lower KOH concentrations. Lattice constant of the KTaO₃ was almost the same as that in JCPDS-PDF, whereas lattice constant of K₂Ta₂O₆ was 0.2% larger than the PDF value.

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Yttria stabilized zirconia (YSZ) films were prepared on Hastelloy-XR alloy substrates by MOCVD at a rate of 100μm h^-1. The effect of yttria content on the thermal shock resistance of YSZ films was investigated at 1273 to 1373 K in air. 4 mol% Y₂O₃-ZrO₂ film in a tetragonal structure showed excellent thermal shock resistance without spalling after 1200 thermal cycles at 1373 K.

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β-Sialon (z=2) particles coated with 10∼20 nm TiN particles were prepared by controlled hydrolysis of Ti(O-i-C₃H₇)₄, followed by nitridation with NH₃ gas. Spark plasma sintering of 25 vol.% TiN/β-Sialon at 1500°C yielded ceramics with TiN networks of 0.1∼0.5μm wide in the matrix, which had a relative density of 95% and a low electrical resistivity (∼10^-4Ωcm).

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Highly oriented In₂O₃ Whiskers were heteroepitaxitially grown on an optically polished (001) plane of the single crystalline substrate of yttria stabilized zirconia(YSZ) using the chemical-vapor-deposition technique employed at the atmospheric pressure. X-ray diffractometry revealed that the epitaxial relationship between the whiskers and the substrate was determined as In₂O₃ [100](001)//YSZ [100](001). In addition, the full-width at half maximum value of the (004) reflection was as low as 0.23°. Images obtained using a scanning electron microscope suggest that the whisker growth develops the elegant side-branch on the edge of the tetragonal columnar structure. The Kossel mechanism is one of the strong candidates for the mechanism of the whisker and side-branch.

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Layered titanate H_1.07Ti_1.73O₄ was exfoliated into nano-sheet by reacting with n-propylamine solution. The H_1.07Ti_1.73O₄ thin film with preferred or ientation can be obtained by dipping a metal substrate in the nano-sheet sol solution and dry. The titanate thin film can topotactically transformed to a titanium oxide thin film with preferred orientation by heat-treatment, and to a BaTiO₃ thin film with preferred orientation by hydrothermal treatment in a Ba(OH)₂ solution.

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Effects of substrate and wavelength on the crystallinity and surface morphology of UV irradiated zirconia thin films were investigated. The surface morphology of alkoxy-derived zirconia thin films changed in case of UV irradiation using an ultra-high pressure mercury lamp at room temperature. On the other hand, the crystallinity of zirconia thin films increased in case of UV irradiation using a low pressure mercury lamp at room temperature. The substrate and wavelength were considered to play important roles in the reaction.

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Hydrophobic-hydrophilic patterned surfaces were prepared by selective UV irradiation through a photomask on multilayered films of TiO₂ and FAS. SnO₂ precursor solution prepared from SnCl₂ and EtOH was coated on the hydrophobic-hydrophilic patterned surfaces. After a heat-treatment at various temperature, convexly shaped SnO₂ patterns were formed on hydrophilic area of the patterned surfaces. Thickness of these patterns was more than 1μm.

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ZnO micropatterns were fabricated by using phenyl/OH-terminated self-assembled monolayer (SAM) template through electroless deposition process only on the regions where the Pd catalyst adhered to the phenyl-surfaces. The deposition process of ZnO on the catalyzed substrates was observed and the mechanism was discussed.

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Mesoporous titania with large surface area was obtained by hydrophobic polystyrene templating. The wet gels prepared by hydrolysis of Ti-alkoxide in THF-solution were immersed in polystyrene solution, dried and calcined. The gel films were prepared from the sols obtained by hydrolysis of Ti-alkoxide in THF solution with addition of polystyrene. The pore size, specific surface area and pore volume of the gels and gel films increased by polymer templating. The pore size distribution and pore shape of the gels depend on the polymer concentration.

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To obtain porous titanium dioxide film, the precursor which contained the sol and trehalose was prepared by sol-gel method. The porous titanium dioxide film was prepared by dip-coating technique on glass substrate with this solution. The film was composed of nano sized particles (20 nm). The maximum thickness of the film prepared by one-run dip-coating was ca. 640 nm.

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Electrophoretic deposition is an effective forming technique to fabricate the dense and porous ceramics. In this study, the green samples of alumina and zirconia ceramics were fabricated by this EPD method. Green bodies prepared by EPD method were sintered by pressureless sintering at 1100∼1300°C. The microstructures were observed by SEM. These results suggested that the porous microstructures were dependent on pH of suspension and current/voltage.

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In order to prepare a bulky zeolite with a monolithic phase (zeolite A), zeolite precursors were synthesized from Al(OH)₃, water glass and metakaolin. The precursor was heat-treated in a hermetic condition at temperatures between 60°C and 200°C. Al(OH)₃ was activated by milling in a dry condition and an effect of mechanochemical phenomena on zeolite phase was examined. When non-milled Al(OH)₃ was used, faujasite phase was synthesized. Activated Al(OH)₃ was found to be very effective to synthesize monolithic zeolite A.

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In the present work, doping effect of zinc on synthesis of gallophosphate molecular sieve, which is generally called as cloverite, with an unique framework structure has been investigated by powder XRD, TG-DTA, SEM and EPMA. SEM has observed that the zinc doping highly promotes crystal growth of cloverite. Powder XRD and EPMA have suggested that the zinc elements are incorporated as a substitute for Ga in the framework.

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Mesoporous silica was prepared by the hydrolysis of tetraethylorthosilicate (TEOS) in the presence of dodecyltrimethylammonium bromide (DTAB) as an organic template at room temperature. The shapes of synthesized products were greatly changed by the compositions of starting materials. The synthetic condition of spherical mesoporous silica using DTAB is severer than that using DDA.

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We have prepared mesoporous silica using DDA as a surfactant and tried to fabricate a composite using a porous alumina matrix to improve the mechanical strength. In conclusion, it has been shown that the composite fabricated from mesoporous silica and porous alumina has a sufficient mechanical strength to enable us to use it for gas separation.

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Silicate foams have been prepared by reaction of HSi(OC₂H₅)₃ with aqueous lithium silicate solution. The gelation occurred immediately and the hydrogen gas during the gelation produced macro-voids to provide silicate foams. The surface of the silicate foams showed the solid basic property of H₀ = 9 and adsorbed the acidic gases of NO and NO₂. FT-IR spectrum showed an absorption peak at 1385 cm^-1 assigned to deformation vibration of nitrate ion, NO^3-.

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Mesoporous silica was prepared by sol-gel method using Si(OC₂H₅)₄ in the presence of organic surfactant. Ti(OC₂H₅)₄ and Al(OC₂H₅)₃ were used as Ti and Al source. The average pore size was 2.5-3.2nm and the specific surface area was 1150-1300m²/g. The mesoporous structure was not changed by the addition of titania and alumina. The acidity of TiO₂-added mesoporous silica exhibited the maximum at a low TiO₂ content and was higher than that of Al₂O₃-added mesoporous silica. This is because the acid strength of TiO₂/SiO₂ system is higher than that of Al₂O₃/SiO₂ system.

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The porous TiO₂-Al₂O₃ powders with large surface area were prepared by surfactant immersion procedure. The specific surface area was nearly the same as that of supercritically dried aerogels after heating at 500°C, and two times larger than that of the samples without surfactant immersion after heating at 800°C. The average pore size and the pore volume were hardly increased by surfactant immersion. However, the pore size distributions depended on the concentration of surfactants.

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Mesoporous silica with high specific surface area is an attractive material in many application fields such as catalysts and adsorbents. TiO₂ has been widely applied for photocatalysts. We successfully prepared mesoporous silica - titania foams by direct spraying precursor solution containing TEOS, surfactant, ammonia, and TiO₂ fine particles with a commercial foaming spray. Surface area and pore volume decreased with an increase in amount of TiO₂ because mesoporous silica particles were replaced with TiO₂ fine particles.

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We report on a search of photopolymerizable sol-gel organic-inorganic films with a higher refractive index and a fabrication of two dimensional periodic microstructures in the film by laser interference technique. The sol-gel films were prepared from organosilicate alkoxide and titanium alkoxide modified by methacrylic acid, which contain the photopolymerizable function. The refractive index of the film increases with the increase of titanium alkoxide. The film with the highest refractive index is exposed to interference light and the unexposed parts are removed. And then a two-dimensional periodic structure, in which the materials are arranged square lattice in about 1.7μm spacing, is produced.

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