Abstract: Bi3 Ti4 O12/α-Bi2 O3/TiO2 composite photocatalyst was prepared by using industrial titanium dioxide (TiO2) and Bismuth nitrate pentahydrate (Bi(NO3)3 · 5H2O) as raw materials.Sample's structures were characterized by XRD , XPS, FT-IR, UV-vis, PL spectrum, etc.The results show that the Bi3 Ti4 O12/α-Bi2 O3/TiO2 heterojunction structure is formed .The band gap decreases , the absorption band edge is red shifted , and the photocatalytic efficiency is obviously improved .The photocatalytic activity was tested for the degradation of methylene blue solution under visible light irradiation .The results show that the photocatalytic activity of La doped TiO 2/g-C3 N4 composite photocatalyst is remarkable when the ratio of commercial titanium dioxide and Bismuth nitrate pentahydrate is 1:2.5, the calcination temperature was 600 ℃and the calcination time was 5 h.Irradiated by 12 W LED with 180 min, the degradation rate of MB reaches 96.8;.

Key words: Bi3 Ti4 O12/α-Bi2 O3/TiO2 composite photocatalyst was prepared by using industrial titanium dioxide (TiO2) and Bismuth nitrate pentahydrate (Bi(NO3)3 · 5H2O) as raw materials.Sample's structures were characterized by XRD , XPS, FT-IR, UV-vis, PL spectrum, etc.The results show that the Bi3 Ti4 O12/α-Bi2 O3/TiO2 heterojunction structure is formed .The band gap decreases , the absorption band edge is red shifted , and the photocatalytic efficiency is obviously improved .The photocatalytic activity was tested for the degradation of methylene blue solution under visible light irradiation .The results show that the photocatalytic activity of La doped TiO 2/g-C3 N4 composite photocatalyst is remarkable when the ratio of commercial titanium dioxide and Bismuth nitrate pentahydrate is 1:2.5, the calcination temperature was 600 ℃and the calcination time was 5 h.Irradiated by 12 W LED with 180 min, the degradation rate of MB reaches 96.8;.