LAUSR

Abstract It is still a great challenge to replace Pt by non-precious metal electrocatalysts toward hydrogen evolution reaction (HER) due to their sluggish kinetics and poor electrochemical durability. Here, we reported a novel two-dimensional Co3W3C nanosheets on graphene nanocomposition (Co3W3C NSs/G) that synthesized by a simple two-step method. The overpotential of Co3W3C NSs/G at 10 mA cm−2 (η10) is just 64 mV in 0.5 M H2SO4 solution, which is very close to Pt/C (37 mV). The Tafel slope of Co3W3C NSs/G is 35 mV dec−1, which is also very close to Pt/C (30 mV dec−1). The exchange current density (j0) of Co3W3C NSs/G is 0.232 mA cm−2, which is almost as high as Pt/C (0.279 mA cm−2). Overall, the Co3W3C NSs/G exhibits Pt-like catalytic activity toward HER. Furthermore, the Co3W3C NSs/G shows outstanding HER activities and extreme high electrochemical durability in a wide pH range. The density functional theoretical (DFT) calculations show that the Gibbs free energy of hydrogen bonding (ΔGH*, * denotes an adsorption site) of the Co3W3C is −0.15 eV, which is also very close to Pt (−0.09 eV).