Tunable Reduction Optimizing Mo2C/Mo2N Heterostructure Enabling Efficient pH-Universal Hydrogen Evolution

The development of safe, low-cost and highly active non-precious metal electrocatalysts plays a vital role in efficient hydrogen production. Herein, Mo 2 C/Mo 2 N heterostructure was in-situ synthesized by a two-step method for excellent hydrogen evolution performance at a universal pH range. The results show that the optimized MoCN-750-2h only needs 86.5, 102.5 and 120.5 mV overpotentials to reach 10 mA·cm −2 in alkaline, acidic and neutral media, respectively. Not only that, MoCN-750-2h had a low Tafel slope (37.2 and 88.5 mV·dec −1 ) in alkaline and neutral media, implying that catalytic kinetic is close to the level of Pt/C. These results can be attributed to reasonable C and N content in MoCN-750-2 h, optimizing the electron cloud distribution of Mo 2 C/Mo 2 N heterostructure to boost hydrogen production. Graphical Abstract MoCN heterostructure was in-situ synthesized by a two-step method for excellent hydrogen evolution performance at a universal pH range. The optimized electron cloud distribution of Mo 2 C/Mo 2 N would promote the formation of electron transfer channels, boosting the hydrogen evolution catalytic activity of the heterostructure. The MoCN heterostructure only needs 86.5,102.5 and 120.5 mV overpotentials to reach 10 mA·cm −2 in alkaline, acidic and neutral media, respectively. Not only that, MoCN-750-2 h had a low Tafel slope (37.2 and 88.5 mV·dec −1 ) in alkaline and neutral media, implying that catalytic kinetic is close to the level of Pt/C.