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Li₂S-P₂S₅-P₂O₅ glass-ceramics were prepared by mechanical milling and subsequent heat treatment. Highly ion-conductive crystals were precipitated in those glass-ceramics, resulting in the enhancement of conductivities. The glass-ceramics with elemental P and S as starting materials showed as high conductivities at room temperature as the ones with P₂S₅. The addition of small amounts of P₂O₅ to Li₂S-P₂S₅ system led to the improvement in conductivity and electrochemical stability. All-solid-state lithium secondary batteries with the glass-ceramic solid electrolytes worked at room temperature and maintained high capacities and high reversibilities.

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Development of all ceramic Solid Oxide Fuel Cell is an important subject from practical application point of view. In this study, anodic property of various oxides was investigated and it was found that CeO₂ doped with Mn exhibits high activity to anodic reaction. The anodic overpotential could be further lowered by doping small amount of Fe. The maximum power density of the cell using LaGaO₃ electrolyte and CeO₂ doped with Mn and Fe for anode exhibits high power density and the maximum power density of the cell can achieve a value of 700 mW/cm² at 1273K.

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The mixture containing CsHSO₄ and CsH₂PO₄ (molar ratio 1:1) was mechanically milled using a planetary ball mill to prepare solid-state proton conductor in the medium temperature range. Cs₅(HSO₄)₃(H₂PO₄)₂ and Cs₃(HSO₄)₂(H₂PO₄) were formed by mechanical milling. These compounds showed high proton conductivity at medium temperatures. In this study, proton conductivities of mechanically milled CsHSO₄-CsH₂PO₄ solid acids with various compositions have been investigated.

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Proton conductive composites composed of cesium hydrogen sulfate (CsHSO₄) or cesium dihydrogen phosphate (CsH₂PO₄) and phosphosilicate gel (PSiG gel) were prepared. The reaction of orthophosphoric acid that derived from phosphosilicate gel and each solid acid produce Cs₂H₅(SO₄)₂(PO₄) in CsHSO₄-PSiG composites and CsH₅(PO₄)₂ in CsH₂PO₄-PSiG composites. These composites showed high conductivities of 10^-3 Scm^-1 at 160 ^oC under dry condition. The characteristics of composites prepared from silica gel and Cs₂H₅(SO₄)₂(PO₄) or CsH₅(PO₄)₂ were compared with those of the composites using phosphosilicate gel.

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Hydrogen pumps using high-temperature proton conductors can be applied to hydrogen separation. This paper reports the hydrogen pumping properties (current efficiency, energy efficiency) of strontium zirconate cells, intending the use for hydrogen separation from reformed gases. Porous platinum, prepared by firing a Pt paste printed on to the electrolyte, had quite low electrocatalitic activity. Palladium electrode much improved energetic and hydrogen transport properties probably due to the hydrogen permeability of the palladium electrode.

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TiO₂ nano-crystals were formed on the sol-gel devised SiO₂-TiO₂ films through hot water treatment at temperatures lower than 100 ºC. Moreover, addition of organic polymers in the gel films, such as PEG, has a great influence on the structure after the treatment. These morphological differences of the crystals affect the function of the films, e.g., photocatalytic activity. Therefore, it is quite important to discuss the effect of the additive species. In this study, we have investigated the morphological changes in the precipitated nanocrystals on the gel films by adding of various organic polymers and supramolecules.

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Zn-Al LDH thin films intercalated with various organic anions were directly prepared on glass substrates by immersion of sol-gel derived amorphous Al2O3-ZnO thin films on glass substrates in distilled hot water with organic salts: sodium dodecyl sulfate, p-toluenesulfate, and benzenecarboxylates. In all the systems, nanocrystals with hexagonal structure were formed on the amorphous thin films by immersion in hot distilled water with and without salts. From the XRD diffractograms of the films obtained, the LDHs with dodecyl sulfate anions and terephthalate ions were easily formed.

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Barium Titanate particles are utilized as a ferroelectric material for many years, and the use as a multi-layered ceramic capacitor has widely spread in recent years. To the trend of decreasing size and increasing capacity, it is especially anxious for the fine barium titanate particles with high dielectric constant. On the other hand, the needs of the Barium titanate particle of nano size are increasing as a thin film or a printing material. We can reached the ultra fine barium titanate of under 20nm size particle from conventional 100nm size particles and the narrower size distribution. This presentation will report focusing on the powder characterisity.

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The electrostrictive resonance phenomena at high frequencies of parallel platecapacitors based on thin film (Ba0.5Sr0.5)TiO3 and (Ba0.7Sr0.3)TiO3dielectric layers with Pt electrodes have been simulated using their acoustic properties and compared with measurement data. The simulation is using a Mason model and a matrix approach. A good correlation between the predicted and measured values has been achieved. The influence of different additional layers (e.g., Pt, ILD, Metal interconnect, etc.) underneath or on top of the BST dielectric (actual capacitor area) as well as the substrate influence (Si or Al2O3 ceramic) have also been analyzed.The main electrostrictive resonance peak is primarily controlled by the Pt electrodes and BST layer thicknesses and it is further split in few new ones, smaller in amplitude and at lower frequencies. The present work gives an important understanding and practical control of the electrostrictive resonances in order to guarantee maximum Q-factor at any bias voltages of the tunable thin film BST capacitors in high frequencies (0.5-10 GHz).

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Researches of relaxors meeted the 50th aniversary since its descovery. Due to huge pezoelectric and dielectric responses, the investigation of relaxors are still quite active and the number of papers are increasing in both fields of applications and fundamentals. In particular, the development of semi-microscopic model and the first principle study is revealing the mecahnism of relaxors. In this talk, we would summarize these kinds of researches and clarify the settled and unsolved problems in relaxors.

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Previous studies on relaxors were reviewed to understand the reason of broad and frequency dependent permittivity peak observed in relaxors. The intermediate region between normal ferroelectrics and relaxors are called as diffuse phase transition (DPT) region. Lead free DPT materials are used for MLCCs and tunable capacitors. Ceramics of BaTiO3-BaZrO3 (BZT) solid solutions and BaTiO3-SrTiO3 (BST) solid solutions were prepared as a sample of lead free relaxors and DPT materials, and dielectric dispersion of these ceramics were measured up to 3 GHz. The difference between BZT and BST was observed as a change of relaxation frequency in the microwave region.

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