| 摘要 |
PROBLEM TO BE SOLVED: To improve the optical activity, catalytic activity, mechanical strengths and durability of a sintered anatase-type titania by quickly sintering anatase-type titania fine powder having respectively specific average particle diameter and particle size distribution at a low temperature for a specific time at a specific maximum holding temperature and converting the crystal form of sintered titania to a polycrystalline material having anatase crystal form. SOLUTION: Anatase-type titania fine powder having an average particle diameter of 5-300 nm and a particle size distribution of 3-500 nm is quickly sintered at a low temperature for 1-15 min in air, vacuum or inert gas atmosphere at a maximum holding temperature of 600-900 deg.C to obtain the objective sintered titania keeping the anatase-type crystal form of the sintered titania. The void ratio of the sintered titania is controlled by the amount of binder such as ethylcellulose to be added in a preliminary forming and the photo- irradiation efficiency is improved by the increase of the surface area per unit volume. The material can be imparted with adsorption function by the mixing, dispersion or gradient distribution of <=20 wt.% of an adsorption functional substance such as zeolite to the polycrystalline sintered titania. |
