Study on Preparation of W,N Codoped TiO₂ Photocatalyst by Low-temperature Sol Process

Taking tetra-n-butyl titanate as precursor and ammonium nitrate and ammonium tungstate as codoping sources,nanoscale W,N codoped TiO₂ powder is directly prepared by low-temperature sol process. The samples are characterized by XRD,SEM,IR,XPS,and GTA. The results show that the spherical codoped photocatalyst powder is anatase TiO₂ with particle sizes of 8.9 nm and good stability below 600℃; the energy gap of the powder is 2.86 eV and the photoresponse moves to the range of visible light. Sunlight is replaced by xenon lamp to degrade methyl orange solution for 60 min,and the degradation rate of the photocatalyst powder reach to 94% or above,which shows a noticeably improved performance than that of P25.