Constructing Ni-VN interfaces with superior electrocatalytic activity for alkaline hydrogen evolution reaction.

The promotional effects of inert nitrides for metal catalysts in the electrolysis are rarely reported. Recently, we reported an efficient Ni-VN/NF (that NF represents Ni foam) composite by nitriding treatment of NiV-layered double hydroxides (NiV-LDH) precursor that was in-situ hydrothermal growth on nickel foam. The optimal Ni-VN/NF exhibited outstanding electrocatalytic performance for hydrogen evolution reaction (HER) with a small overpotential of 39 mV at 10 mA cm and strong durability for 100 h without degradation. The optimized electronic structure and local charge density at the hetero-interface of Ni-VN, evidenced by both experiment and DFT results, were significantly modulated by the electron transfer from Ni to V-N bond at the interfaces, leading to moderate H* adsorption energy and diminished barrier for HO dissociation, synergistically promoted basic HER. This work highlights the design principle of strong metal-nitride interactions for advanced HER catalysts.