Lithium-sulfur batteries are expected for the energy storage devices of renewable energy because of low cost and high capacity. However, the insulating property of sulfur is one of the challenges for their practical application. We synthesized silica nanoparticles-templated porous carbon (STPC) as a conductive material for the lithium-sulfur battery. Pore size and specific surface area of STPC were able to control by selecting size of silica nanoparticles. STPC synthesized with silica nanoparticles of 5 nm in diameter showed high specific surface area (1435 m²・g^－1) and retention of charge-discharge capacity after 20 cycles, while STPC synthesized with silica nanoparticles of 50 nm in diameter showed high initial discharge capacity (841 mA・h・g^－1). As the diameter of silica nanoparticles increased, the initial discharge capacity increased and the capacity retention rate decreased. Using silica nanoparticles of different diameter improved the capacity decay.

　In order to obtain a fluorescent material that emits white light with a high color rendering property, an attempt was made to synthesize a phosphor based on strontium aluminate as the matrix crystal. Synthesis in an air atmosphere resulted in fluorescent materials based on a mixed phase of SrAl₁₂O₁₉ and Sr₄Al₁₄O₂₅. By irradiating the obtained mixed phases with an excitation wavelength of 365 nm, red luminescence derived from Eu³⁺ ions was simultaneously obtained from SrAl₁₂O₁₉ and blue-green luminescence derived from Eu²⁺ ions from Sr₄Al₁₄O₂₅. The Eu²⁺ ions in Sr₄Al₁₄O₂₅ were obtained by a reduction reaction during calcination in an air atmosphere. The obtained luminescence color varied from red to white depending on the synthesis conditions, and (0.357, 0.348) was obtained as the chromaticity coordinate closest to the white point. Two types of fluorescent materials based on strontium aluminate matrix crystals were obtained in a single synthesis, and white luminescence with excellent color rendering was obtained by simultaneous luminescence.