Heterojunction Mo-based binary and ternary nitride catalysts with Pt-like activity for the hydrogen evolution reaction

The development of earth-abundant electrocatalysts with Pt-like catalytic activity for the hydrogen evolution reaction (HER) is of great significance to green hydrogen production. Herein, a novel strategy is described to construct dual-phase nitride nanobelts composed of Mo2N and Ni0.2Mo0.8N by nitridation of Ni2+ intercalated layered MoO3 nanobelts (NBs). The Mo2N/Ni0.2Mo0.8N catalyst exhibits superior stability and a low overpotential of 26 mV at 10 mA cm−2 and Tafel slope of 31 mV dec−1 in both the alkaline electrolyte and simulated seawater, which is comparable to or better than that of the benchmark Pt/C catalyst. The excellent alkaline HER characteristics is attributed to the Mo2N/Ni0.2Mo0.8N heterostructure with adjustable content and robust interfaces and without metal Ni segregation and structure collapse during nitridation. Density-functional theory (DFT) calculations and experiments reveal that the Mo2N/Ni0.2Mo0.8N interface with strong electronic interactions optimizes H adsorption/desorption yielding moderately weak bonding metal sites with positive ΔGH* as the catalytic centers, thereby accelerating the HER kinetics and boosting the HER activity. The results reveal a simple strategy for the preparation of heterostructured nitride-based catalysts with Pt-like activity for hydrogen evolution.