Abstract: We investigated the photovoltaic properties of series of TiO₂ photocatalysts by means of SPS and found that the thresholds of TiO₂ particles blue shift with their particle sizes decreasing and crystal phases changing from rutile TiO₂ to anatase TiO_2. Combining with the photodegradation activities of TiO₂ on C₇H₁₆, it was concluded that the photocatalytic activities of TiO₂ increase with their thresholds increasing,which can be explained using energy band theory. We also investigated the relationship beween the photovoltaic properties and photocatalytic activities of B TiO₂ before and after photooxidation on C₇H₁₆, SO₂ and C₇H₁₆ +SO₂, respectively and found adsorbates at the surface of TiO₂ affect their photocatalytic activities and conduction types of surface layer.

Key words: TiO₂, Photocatalysis, SPS, Photodegradation