Mo doping-induced edge amorphization of CuSe nanosheets to boost hydrogen evolution reaction in neutral media

The development of efficient electrocatalysts for hydrogen evolution reaction (HER) in neutral media remains a challenge due to their slow kinetics and low conductivity. Metal selenides are widely used as HER catalysts, but their structural stabilities are not good and the HER performances in neutral media need to be improved. Herein, we report the direct growth of Mo-doped CuSe (Mo 0.33 Cu 0.67 Se) nanosheets with edge-amorphization on Ni foam (NF) through a facile one-pot solvothermal method for the first time, which are inexpensive and possess high-HER performances in neutral media. It was found that Mo 0.33 Cu 0.67 Se only requires an overvoltage of 55 mV to reach a current density of 10 mA cm −2 (with a Tafel slope of 75 mV dec -1 ), which is superior to commercial 20 % Pt/C (73 mV). Doping CuSe with Mo could lead to amorphization of the edges of nanosheets, and both experimental and theoretical results verify that this structure is beneficial for reducing the oxidative dissolution of Se ion and improving stability. Meanwhile, it also optimizes the free energy of H 2 O dissociation, hydrogen adsorption and desorption, thereby effectively enhancing the performance of electrocatalytic hydrogen evolution in neutral media.