Sol-gel Synthesis and Photocatalytic Activity of La₂Ti₂O₇/HZSM-5

Abstract

La2Ti2O7/HZSM-5 photocatalysts were prepared by sol-gel method, and its photocatalytic activity was studied. The results show that the original crystal phase of La2Ti2O7 is not changed after loading La2Ti2O7 on HZSM-5,and is still perovskite structure. La2Ti2O7 is dispersed on the surface of HZSM-5 after loading to apparent increasing specific surface area and formation of new mesoporous structure. The growth of La2Ti2O7 is constrainted by HZSM-5, resulting in the reduction of grain size. The absorption boundary has a blue shift and the band gap increases with decreasing La2Ti2O7 loading content. Binding energies of La3d and O1s electrons move to higher energy after loading La2Ti2O7 on HZSM-5. La2Ti2O7/HZSM-5 has enhanced photocatalytic activity as compared to La2Ti2O7. 91.8% of the reactive brilliant red(RBR) X-3B is decolorized on 70%La2Ti2O7/HZSM-5 after 120min of UV irradiation, while only 31.7% of the dye is removed on La2Ti2O7.

Keywords

• sol-gel
• lanthanum titanate
• HZSM-5
• photocatalysis