Effective charge separation through the sulfur vacancy interfacial in n-CdO/p-CdS bulk heterojunction particle and its solar-induced hydrogen production

The composites are still worth researching, because the catalytic performance greatly varies depending on the ways when two or more particles are grafted. In this study, we report a n-CdO/p-CdS bulk heterojunction (BHJ) nanostructures with abundant sulfur vacancy defects to improve the photoexcited charge separation during the photocatalytic reactions. The n-CdO/p-CdS nanostructured photocatalyst exhibits extended visible light absorption, reduced electron-hole recombination rate and improved photoexcited charge carriers generation, transfer and separation capability. Moreover, electronic band differences between the CdS and Cd0 bulk junctions creates the sulfur vacancies via CdSO3. The hydrogen production amount of the 1CdO/2CdS catalyst (1.2 mu mol.g(-1)) shows a remarkable performance that is 10 times higher than that of the CdO (0.02 mu mol.g(-1)) and CdS (0.07 mu mol.g(-1)) single particle catalysts. The improved photocatalytic activity can be ascribed to the intimate interfacial contact between CdS and CdO nanostructures, sulfur vacancies and efficient charge carrier separation. (C) 2020 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.