Hierarchical composite structure of few-layers MoS 2 nanosheets supported by vertical graphene on carbon cloth for high-performance hydrogen evolution reaction

• DOI: 10.1016/j.nanoen.2015.10.014
• Publication Date: 2015-11-04T10:19:15Z
• Authors: Zhenyu Zhang; Wenyue Li; Muk Fung Yuen; Tsz-Wai Ng; Yongbing Tang; Chun-Sing Lee; Xianfeng Chen; Wenjun Zhang
• Keywords: Overpotential; Molybdenum disulfide

Abstract Here we report a hierarchical composite structure composed of few-layers molybdenum disulfide nanosheets supported by vertical graphene on conductive carbon cloth (MDNS/VG/CC) for high-performance electrochemical hydrogen evolution reaction (HER). In the fabrication, 3D vertical graphene is first prepared on carbon cloth by a micro-wave plasma enhanced chemical vapor deposition (MPCVD) and then few-layers MoS 2 nanosheets are in-situ synthesized on the surface of the vertical graphene through a simple hydrothermal reaction. This integrated catalyst exhibits an excellent HER electrocatalytic activity including an onset potential of 50 mV, an overpotential at 10 mA cm −2 ( η 10 ) of 78 mV, a Tafel slop of 53 mV dec −1 , and an excellent cycling stability in acid solution. The excellent catalytic performance can be ascribed to the abundant active edges provided by the vertical MoS 2 nanosheets, as well as the effective electron transport route provided by the graphene arrays on the conductive substrate. Moreover, the vertical graphene offers robust anchor sites for MoS 2 nanosheets and appropriate intervals for electrolyte infiltration. This not only benefits hydrogen convection and release but also avoids the damaging or restacking of catalyst in electrochemical processes.