Mo 2 C coated with Ni nanoparticles as the cathode catalyst towards efficient hydrogen evolution reaction: an experimental and computational investigation.

Although Mo 2 C and earth-abundant 3d transition metals are regarded as potential catalysts to replace noble metal catalysts for effective hydrogen evolution reaction, their large-scale application is still inhibited by their own defects. Here, a facile thermal treatment method for nonprecious metal catalysts is developed to prepare a porous Ni/Mo 2 C composite catalyst. The loading density of Ni nanoparticles on the Mo 2 C surface has an important effect on the activity of the catalyst. By optimizing the Ni doping ratio, the Ni-40/Mo 2 C-17 sample exhibits the lowest onset overpotential and lowest overpotential at 10 mA cm -2 in both acidic and alkaline electrolytes, compared to other reported Ni- and Mo 2 C-based catalysts. In addition, theoretical calculations have also confirmed the synergistic effect between Ni nanoparticles and Mo 2 C, which can balance the thermodynamics between H adsorption and desorption of H 2 . This work provides an avenue for designing high-performance water-splitting catalytic materials using low-cost species, which exhibit excellent HER activity in a wide pH range.