Fabrication of a Cu2O/g‐C3N4/WS2 Triple‐Layer Photocathode for Photoelectrochemical Hydrogen Evolution

• Published in: ChemElectroChem Vol. 4; no. 6; pp. 1498 - 1502
• Main Authors: Xu, Xintian, Liu, Yizhe, Zhu, Yuanzhi, Fan, Xiaobin, Li, Yang, Zhang, Fengbao, Zhang, Guoliang, Peng, Wenchao
• Format: Journal Article
• Language: English
• Published: Weinheim John Wiley & Sons, Inc 01-06-2017
• Subjects: Alloys; Assembly; Carbon nitride; Catalysts; Conversion; Copper oxides; Efficiency; Electricity; exfoliation; Hydrogen; Hydrogen evolution; Insertion; Lithium; mixed-phase WS2; Nanostructure; Nickel; P-n junctions; Photoelectric effect; Photoelectric emission; photoelectrochemistry; triple-layered photocathodes; tungsten disulfide
• ISSN: 2196-0216; 2196-0216
• DOI: 10.1002/celc.201700014

A Cu2O/g‐C3N4/WS2 triple‐layer photocathode was fabricated by using a layer‐by‐layer assembly method for photoelectrochemical hydrogen evolution. Cu2O was electrodeposited on the FTO as the active layer for light harvesting. The chemically inert g‐C3N4 can protect the unstable Cu2O layer and form a p‐n junction with Cu2O to increase the light‐to‐electricity conversion efficiency. Mixed‐phase WS2 nanosheets were obtained through a lithium insertion method and used as an effective hydrogen evolution catalyst for photocurrent‐to‐hydrogen conversion. This photocathode is effective for photoelectrochemical hydrogen evolution, and a photocurrent of −9.5 mA cm−2 at −0.55 V versus RHE (pH 6.0) can be obtained under visible light (λ≥420 nm, 100 mW cm−2).
High–light: A Cu2O/g‐C3N4/WS2 triple‐layer photocathode is fabricated by using a layer‐by‐layer assembly method with Cu2O as the light harvester, g‐C3N4 as the protective layer, and exfoliated mixed‐phase WS2 as the hydrogen evolution catalyst. A high light‐to‐hydrogen conversion efficiency can be obtained with a low overpotential and a large photocurrent.