Simulated-sunlight-activated photocatalysis of Methyl Orange using carbon and lanthanum co-doped Bi2O3-TiO2 composite

The C/La/Bi2O3-TiO2 composite was prepared by sol-gel method. The physicochemical properties of as-synthesized samples were characterized by the TG-DSC, FESEM, EDS, XRD, XPS, TEM, HRTEM and UV-vis DRS. Besides, their photoactivities were valuated by degrading Methyl Orange. The experimental results showed that the C/La/Bi2O3-TiO2 composite has anatase crystal structure and exhibits a remarkable optical absorption in UV-visible light region. In addition, carbon and lanthanum are deposited in the Bi2O3-TiO2 composite in the form of amorphous carbon and oxide, respectively. When the concentration of C/La/Bi2O3-TiO2 loading was 2.5 g/L, the decomposition rate of 25 mg/L Methyl Orange reached 94.3% under the irradiation of the 500 W xenon lamp after 60 min. The corresponding degradation rate constant of C/La/Bi2O3-TiO2 was 2.1, 9.2, 1.3 and 6.8 times higher than that of P25, Bi2O3-TiO2, C/Bi2O3-TiO2 and La/Bi2O3-TiO2, respectively. The reuse evaluation of C/La/Bi2O3-TiO2 indicated that its photocatalytic activity has good stability. (C) 2016 Elsevier B.V. All rights reserved.