The preparation of porous nano-TiO_2 with high activity and the discussion of the cooperation photocatalysis mechanism

摘要

The material of porous nano-TiO_2 was prepared with a new preparation method. The relations between the crystalloid and the size of TiO_2 nanograin and the technics conditions were studied. The control of TiO_2 nanograin was discussed initially. It has very high photocatalytic activity. The degradation rate of the methyl orange solutions (50 mg L~(-1)) which were decomposed by nano-TiO_2 in the irradiation of the ultraviolet high-voltage mercury lamp whose main wavelength is 365 nm only in 17 min was above 99.6%. After stopping irradiation, there is a degradation dark-reaction whose reaction rate is rapid at first and then slow down. The standpoint that in the anatase TiO_2 there are thimbleful rutile TiO_2 which could bring the cooperation photocatalysis degradation and improve its photocatalytic activity was first put forward.