Heterostructured Mo2N-Mo2C Nanoparticles Coupled with N-Doped Carbonized Wood to Accelerate the Hydrogen Evolution Reaction

Mo2C is a promising non-precious hydrogen evolution reaction (HER) electrocatalyst. However, regulating the strong hydrogen adsorption characteristics of Mo2C and finding suitable support electrodes are essential processes before Mo2C can replace Pt to realize a sustainable hydrogen economy. Herein, the facile synthesis of heterostructured Mo2N-Mo2C nanoparticles on N-doped carbonized wood (Mo2N-Mo2C/N-CW) as a self-supported electrode through carbonization and NH3 plasma treatment is demonstrated. The synergistic effects of heterostructured Mo2N-Mo2C and N-CW with aligned microchannels provide enhanced catalytic activity, fast charge transfer kinetics, additional active site exposure, and rapid transport of the electrolyte and H-2 bubbles, which improves the HER performance. Consequently, the Mo2N-Mo2C/N-CW electrode exhibits superior HER performance with low overpotentials of only 79 and 311 mV to reach 10 and 500 mA cm(-2) in an acidic solution, respectively. It also exhibits long-term stability for 20 h in the high-current-density region (110 mA cm(-2)). The density functional theory (DFT) calculations at various sites reveal that the heterointerface of Mo2N and Mo2C promoted the catalytic activity by optimizing the adsorption/desorption of hydrogen.

Automated summary

In this study, heterostructured Mo2N-Mo2C nanoparticles on N-doped carbonized wood (Mo2N-Mo2C/N-CW) were synthesized as a self-supported electrode through carbonization and NH3 plasma treatment. The synergistic effects of heterostructured Mo2N-Mo2C and N-CW enhanced the catalytic activity, charge transfer kinetics, active site exposure, and electrolyte and H2 bubble transport, resulting in improved hydrogen evolution reaction (HER) performance.