Three-dimensional structure of WS 2 /graphene/Ni as a binder-free electrocatalytic electrode for highly effective and stable hydrogen evolution reaction

• DOI: 10.1016/j.ijhydene.2017.01.089
• Publication Date: 2017-02-04T23:30:15Z
• Authors: Fei Qi; Pingjian Li; Yuanfu Chen; Binjie Zheng; Jingbo Liu; Jinhao Zhou; Jiarui He; Xin Hao; Wanli Zhang
• Keywords: Overpotential; Tungsten disulfide; Reversible hydrogen electrode; Graphene foam

Abstract Tungsten disulfide (WS 2 ) has attracted much attention as the promising electrocatalyst for hydrogen evolution reaction (HER). Herein, the three-dimensional (3D) structure electrode composed of WS 2 and graphene/Ni foam has been demonstrated as the binder-free electrode for highly effective and stable HER. The overpotential of 3D WS 2 /graphene/Ni is 87 mV at 10 mA cm −2 , and the current density is 119.1 mA cm −2 at 250 mV overpotential, indicating very high HER activity. Moreover, the current density of 3D WS 2 /graphene/Ni at 250 mV only decreases from 119.1 to 110.1 mA cm −2 even after 3000 cycles, indicating a good stability. The high HER performance of 3D WS 2 /graphene/Ni binder-free electrode is superior than mostly previously reported WS 2 -based catalysts, which is attributed to the unique graphene-based porous and conductive 3D structure, the high loading of WS 2 catalysts and the robust contact between WS 2 and 3D graphene/Ni backbones. This work is expected to be beneficial to the fundamental understanding of both the electrocatalytic mechanisms and, more significantly, the potential applications in hydrogen economy for WS 2 .