アナターゼ型チタニア固溶体ナノ粒子の性質に及ぼす調製条件の影響

Abstract

Anatase-type titania solid solution nanoparticles doped with niobium and aluminum (Ti1_xNbxA1xO2) were synthesized under various hydrothermal conditions. The effects of hydrothermal treatment temperature and the presence of various additive agents in the precursor solution on the crystallite growth and morphology of anatase and photocatalytic activity were investigated. The crystallite growth of anatase was controlled by the presence of sodium carbonate and sodium citrate. Many of elongated particles were observed in the precipitates obtained in the presence of aqueous ammonia although elongated particles were not detected in the sample prepared using the hydrolysis of urea. Their photocatalytic activity and adsorptivity were evaluated separately by the measurement of the concentration of methylene blue (MB) remained in the solution in the dark or under UV-light irradiation. The anatase solid solution (T0.80Nb0.10Al0.10O2) prepared under hydrothermal condition at 240℃ for 5 h in the presence of aqueous ammonia showed two times higher photocatalytic activity than that of commercially available anatase-type pure TiO2 (ST-01).