Synergistic Effect of Nitrogen/Phosphorus Co-Doping and Molybdenum Carbide Induced Electron Redistribution of Carbon Layer to Boost Hydrogen Evolution Reaction^†

The development of highly efficient non-precious-metal-based electrocatalysts for the hydrogen evolution reaction is imperative for promoting the large-scale application of electrochemical water splitting. Herein, nitrogen/phosphorus co-doped carbon nanorods encapsulated Mo₂C nanoparticles (Mo₂C@PNC) have been prepared by pre-phosphating treatment in combination of the coordination with polydopamine and the subsequent pyrolysis. The phosphating temperature has a significant effect on the content of phosphorus within the resultant Mo₂C@PNC, and the optimal catalyst delivers superior HER activity with the low overpotential of 104 mV at a current density of 10 mA·cm^–2 and good stability for 8 h, which has been theoretically demonstrated to originate from the synergistic effect between P doping and Mo₂C induced electron redistribution of nitrogen-doped carbon layer.