Extremely high photocatalytic H2 evolution of novel Co3O4/Cd0.9Zn0.1S p–n heterojunction photocatalyst under visible light irradiation

Yanling Han, Zhibin Liang, Haifeng Dang, Xinfa Dong

Index: 10.1016/j.jtice.2018.03.035

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Abstract

The transfer and separation of charge carriers in space are vital for photocatalytic water splitting toward the H2 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 H2 evolution (139.78 mmol/g/h) over Co3O4/Cd0.9Zn0.1S-2 without any noble metal co-catalyst was obtained under visible light irradiation (λ ≥ 420 nm), 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% (λ = 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.