【Abstract】 The influence of the baked temperature for TiO 2 ultrafine particles on the photocatalytic oxidation reaction of SO 2 was investigated. The photocatalytic activity of TiO 2 baked at 320 ℃ is higher than that at other temperatures(480 ℃, 550 ℃). It may be explained by the surface state of TiO 2, increasing the content of surface hydroxyl is helpful to enhance the photocatalytic activity. According to the experimental results, the first order kinetic reaction and the mechanism of the reaction were suggested, also the rate constants and half life time were reported.更多还原