The Pt-doped TiO2 powder was prepared by the sol-gel method, and its structure and light absorption performance were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, UV-Vis absorption spectroscopy and X-ray diffraction. The results showed that there were Ti, O, Pt and C elements in the Pt/TiO2 powder, and Pt mainly existed in a metallic state. When calcined between 573 and 873 K, TiO2 in Pt/TiO2 powder took an anatase structure. When calcined at 973 K, 6.3% TiO2 was transformed into rutile structure. The grain size of Pt/TiO2 powder was small. Pt and anatase TiO2 particles were all nanometer particles. With increasing the calcination temperatures, the grain size of TiO2 in Pt/TiO2 powder increased gradually, and the changing of crystal lattice constants a and c differed in different directions. Cell volume was contracted during phase transition. The crystal lattice constant and cell volume of TiO2 with both structures in Pt/TiO2 powders become bigger than those in TiO2 powders. After platinum doping, the photon excited wavelength of TiO2 powder was broadened to visible light region. The basis of visible photocatalysis was realized.

Key words: platinum, titanium dioxide, powder, characterization