LI Guihua ,WANG Anfeng ,CAO Qiming,WANG Zhibin

(Faculty of Chemistry and Material, Langfang Teacher's College, Langfang 065000)

Abstract: La-Co co-doped TiO₂ nanopaticles were prepared via sol -gel process and characterized by DTA and XRD. Their degradation performance of methylene blue under 9W ultraviolet lamp was investigated. The effects of La doping，La-Co codoping and catalyst concentration on their photocatalytic performance were studied. Results indicated that La-Co co-dopedTiO₂showed markedly higher photocatalytic activity than that of TiO₂ and La single doped TiO₂. TiO₂ co-doped with 0.125% La and 0.04% Co showed the highest photocatalytic efficiency. Using this catalyst when the catalyst concentration was 0.60 g/L，the reaction temperature was 40 ℃ and pH was 5.33, the degradation rate in 50min could reach 100%.

Keywords: sol-gel method, nano TiO₂, co-doping, photocatalysis