Enhanced photo-Fenton activity of Sm2O3-NiO heterojunction under visible light irradiation

Sm2O3-NiO (Sm-Ni) heterojunction was prepared by the sol-gel route for the photo-Fenton degradation of RhB in visible light region. In contrast with single phase Sm2O3 and NiO, the enhanced photocatalytic activity was achieved by Sm-Ni composites. Among the Sm-Ni composites, Sm-1-Ni-2 with the Sm/Ni molar ratio of 1:2 and the average dimeter of 70 nm exhibited the best photocatalytic activity. center dot O-2(-) radical plays a vital role in the photocatalytic activity of Sm-1-Ni-2 composites. The reduced band gap energy of Sm-1-Ni-2 composites is favorable for the visible-light harvesting, and the tight interface of Sm2O3 and NiO strengthen the transfer and mobility of charge carries, leading to the high resistance to the recombination of photo-produced electron-hole pairs. (C) 2019 Elsevier B.V. All rights reserved.