Synergistic Interlayer and Defect Engineering in VS2 Nanosheets toward Efficient Electrocatalytic Hydrogen Evolution Reaction

Junjun Zhang; Chenhui Zhang; Zhenyu Wang; Jian Zhu; Zhiwei Wen; Xingzhong Zhao; Xixiang Zhang; Jun Xu; Zhouguang Lu

doi:10.1002/smll.201703098

Synergistic Interlayer and Defect Engineering in VS₂ Nanosheets toward Efficient Electrocatalytic Hydrogen Evolution Reaction

Small. 2018 Mar;14(9). doi: 10.1002/smll.201703098. Epub 2017 Dec 27.

Authors

Junjun Zhang^{1

2}, Chenhui Zhang³, Zhenyu Wang¹, Jian Zhu¹, Zhiwei Wen¹, Xingzhong Zhao², Xixiang Zhang³, Jun Xu⁴, Zhouguang Lu¹

Affiliations

¹ Shenzhen Key Laboratory of Hydrogen Energy and Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, P. R. China.
² School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China.
³ Physical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia.
⁴ School of Electronic Science and Applied Physics, Hefei University of Technology, Hefei, 230009, P. R. China.

PMID: 29280269
DOI: 10.1002/smll.201703098

Abstract

A simple one-pot solvothermal method is reported to synthesize VS₂ nanosheets featuring rich defects and an expanded (001) interlayer spacing as large as 1.00 nm, which is a ≈74% expansion as relative to that (0.575 nm) of the pristine counterpart. The interlayer-expanded VS₂ nanosheets show extraordinary kinetic metrics for electrocatalytic hydrogen evolution reaction (HER), exhibiting a low overpotential of 43 mV at a geometric current density of 10 mA cm^-2 , a small Tafel slope of 36 mV dec^-1 , and long-term stability of 60 h without any current fading. The performance is much better than that of the pristine VS₂ with a normal interlayer spacing, and even comparable to that of the commercial Pt/C electrocatalyst. The outstanding electrocatalytic activity is attributed to the expanded interlayer distance and the generated rich defects. Increased numbers of exposed active sites and modified electronic structures are achieved, resulting in an optimal free energy of hydrogen adsorption (∆G_H ) from density functional theory calculations. This work opens up a new door for developing transition-metal dichalcogenide nanosheets as high active HER electrocatalysts by interlayer and defect engineering.

Keywords: VS2; hydrogen evolution reaction; interlayer expansion; nanosheets; transition-metal dichalcogenides.

Publication types

Research Support, Non-U.S. Gov't