Extremely high photocatalytic H-2 evolution of novel Co3O4/Cd0.9Zn0.1S p-n heterojunction photocatalyst under visible light irradiation

The transfer and separation of charge carriers in space are vital for photocatalytic water splitting toward the H-2 evolution when the semiconductor photocatalyst is excited with solar light. Herein, a novel Co3O4/Cd0.9Zn0.1S p-n heterojunction composite was successfully prepared through facile solvothermal method. The extremely high H-2 evolution (139.78 mmol/g/h) over Co3O4/Cd0.9Zn0.1S-2 without any noble metal co-catalyst was obtained under visible light irradiation (lambda >= 420nm), which was 15.88 times higher than that obtained over the bare Cd0.9Zn0.1S and the apparent quantum efficiency (AQE) reached up to 23.21% (lambda = 420 nm). The characterization results demonstrated that the existence of p-n heterojunction at the contact interface of p-Co3O4 and n-Cd0.9Zn0.1S as well as the incremental photo-absorption were the origin of the outstanding photocatalytic activity. (C) 2018 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.