Iron(III)-doped TiO2 nanopowders with mean particle size of 5070 nm have been synthesized by the plasma oxidative pyrolysis method having advantages of full crystallization, controlled dopant concentration and uniform dopant distribution. Under UV irradiation, the photocatalytic reactivity of the undoped TiO2 was much higher than the doped TiO2, suggesting that iron doping in TiO2 with mean particle size of approximately 60 nm was detrimental to the photocatalytic decomposition of methyl orange in water. Whereas, under visible light irradiation, the iron-doped TiO2 with moderate iron doping concentration showed higher photocatalytic activity than the undoped TiO2 although the reactivity of those having both low and high doping concentrations was lower.

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Eu3+-doped TiO2 luminescent nanoparticles have been synthesized in this work via Ar/O2 thermal plasma oxidizing mists of liquid precursors containing titanium tetra-n-butoxide and europium nitrate. The resultant nanopowders are mixtures of the anatase and rutile polymorphs, but the rutile fraction increases steadily at a higher Eu3+ addition. The solubility of Eu3+ in the TiO2 lattice was limited to 0.5at%. UV-Vis, excitation, and PL studies confirmed the existence of nonradiative energy transfer from the host lattice to the guest ions. As a consequence of this, bright and pure red emission was observed from the nanopowders.

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A method for fabricating polyvinylpyrrolidone (PVP) thin films containing barium titanate (BT) nanoparticles on electrodes is proposed. The BT particles that had an average size of ca. 9nm and a tetragonal crystalline phase were prepared with complex alkoxide methods. PVP/ethanol/water solution suspending the BT particles were spin-coated on ITO glass substrates. The obtained PVP films dispersing the BT particles had thicknesses of 500-1250nm. Their dielectric constants were in a range of 18-28, which corresponded to capacitance of ca.25nF/cm² .

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A method for direct patterning of dielectric BaTiO₃ (BT) films is proposed, which applies lased-induced pyrolysis (LIP) method for BT crystallites-seeded sol-gel BT films with the use of polyvinylpyrollidone (PVP) as stabilizer for BT particles dispersed in precursor solution. An Ar ion laser beam was focused and scanned on the sol-gel-derived films, which induced pyrolysis and crystallization of the films with spatially selectivity. Micropatterns with a width of ca. 5 micrometer of crystalline BT films were well formed at PVP concentration of 25 g/l - 50 g/l.

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The hopping behavior of oxygen between neighboring sites in crystal structures is examined by using the anelastic measurement of ZrO2-Y2O3 ceramics.

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Effect of alkaline addition to CsHSO4 on the conductivity is examined.

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Sintering behavior of the mixtures of coal fly ash (CFA) and basic magnesium carbonate (BMC) was investigated to obtain cordierite ceramics. CFA and BMC were mixed in a mass ratio of 0-50%. Mixtures which added alumina to adjust to the stoichiometric composition of cordierite were similarly prepared. The green compacts were fired in air between 1100-1400C. Ceramics which consisted of cordierite and glass phase were obtained. The cordierite content in ceramics was almost equal to the value calculated from the composition of the green compacts. Apparent porosity and three point bending strength were 10-30% and 55-87MPa respectively.

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The effects of pretreatment of substrate were studied to improve the deposition rate in the nearby vaporization chemical vapor deposition (NV-CVD). The density of the ZnO particles rose, and that grain diameter became small when it was compared with the case of the untreated and pretreatment on the substrate. When ZnO crystal nucleus were formed by pretreatment, the deposition rate of ZnO improved from 0.58 nm min^-1 in the un-management to 45 nm min^-1.

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Lattice defects in AlN ceramics were investigated by positron annihilation life time measurement system (PAL).

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A novel processing route for fabricating microcellular silicon oxycarbide ceramics from a polysiloxane has been developed, recently. The strategy for making the microcellular ceramics involves: (i) forming some shapes with a mixture of a polysiloxane, expandable microspheres, and optional inert fillers, (ii) foaming the compact by heating, (iii) cross-linking the foamed body, and (iv) transforming the foamed body into microcellular ceramics by pyrolysis. By controlling the microsphere content and the pyrolysis temperature, it was possible to adjust the porosity ranging from 50% to 90%. Thermal stability and thermal conductivity of the microcellular silicon oxycarbide ceramics were characterized in the present study. Variations of the flexural and compressive strengths of the microcellular ceramics with porosity were also investigated.

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Recently, our research group found that spongy platinum nanosheets are obtained by reducing Pt salts with sodium boron hydride (SBH) within mixed-surfactant liquid crystal templates. In this study, an attempt was made to load such Pt nanosheets on carbon-support with keeping the nano-structure. Electrochemical study revealed that the spongy Pt nanosheets loaded carbon has large electrochemically active surface area of Pt, and fairly high in electrochemical oxidation and reduction activity. Especially, the observed oxygen reduction activity was higher than that of commercially available ones.

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