Transition Metal Dichalcogenide Anchored in 3D Nickel Framework with Graphene Support for Efficient Electrocatalytic Hydrogen Evolution

Abstract

Abstract Transition metal dichalcogenides (TMDCs), MoS 2 , and WS 2 have emerged as low‐cost and earth‐abundant electrocatalysts for hydrogen evolution reaction (HER). In this work, electrocatalytic HER performance of these TMDCs, supported by few layered graphene and loaded on a 3D framework of Ni foam (Gr/NF), is reported. The graphene in Gr/NF is prepared from inexpensive camphor by atmospheric pressure chemical vapor deposition. The graphene‐supported TMDCs anchored on the Ni foam are demonstrated with a low overpotential for HER below 200 mV at a current density of 10 mA cm −2 which is comparable to their edge terminated counterparts and surpassing that of unsupported bulk or amorphous TMDCs. In addition, their small Tafel slopes (95 and 83 mV dec −1 for MoS 2 ‐ and WS 2 ‐based Gr/NF electrocatalysts, respectively), charge transfer resistance, and long‐term stability make them promising non‐noble electrocatalysts. First principle investigations of the (Mo/W)S 2 /Gr/NF heterostructure shows that their enhanced electrocatalytic activity can be attributed to the d‐band shift in the transition metals, Mo/W (a larger shift for WS 2 ) by Ni, promoting unoccupied antibonding orbitals which facilitate the hydrogen adsorption–desorption process.