Preparation of Porous TiO₂ Photocatalyst by Hydrothermal Crystallizing Process

Porous TiO₂ photocatalyst was prepared via hydrothermal crystallization of industrial metatitanic acid,and the effects of crystallization time on structures and properties of porous TiO₂ were also investigated.The samples so prepared were characterized by XRD,SEM,XPS,FT- IR and nitrogen absorption-desorption,and its photocatalytic activity was evaluated by photocatalytic degradation of methylene blue.With the extension of the crystallization time,the photocatalytic activity increased initially and then gradually decreased.Porous TiO₂ crystallized at 140℃ for 2 h showed the best photocatalytic activity,with the degradation rate of 81.18% 1 h after reaction.And its specific surface area S_BET,pore volume V_P,average pore size D_BJH and crystal size are 99.59 m²/g,0.271 cc/g,3.809 nm and 17.79 nm respectively.