Highly efficient electrocatalysts towards hydrogen evolution reaction (HER) with large current density at all-pH values are critical for the sustainable hydrogen production. Herein, we report a free-standing HER electrode, phosphorous-doped molybdenum nitride nanoparticles embedded in 3-dimentional carbon nanosheet matrix (P-Mo₂N-CNS) fabricated via one-step carbonization and in-situ formation. The as-prepared catalyst shows free-standing architecture with interconnected porous microstructure. P-doped Mo₂N nanoparticles with an average diameter of 4.4 nm are well embedded in the 3-dimentional vertical carbon nanosheets matrix. Remarkable electrocatalytic HER performance is observed in alkaline, neutral and acidic media at large current densities. The overpotential of P-Mo₂N-CNS to drive a current density of 100 mA cm⁻² in 0.5 M H₂SO₄ and 1.0 M PBS is only 181 and 221 mV, respectively. In particular, the current density reaches up to 1000 mA cm⁻² at a low overpotential of 256 mV in 1.0 M KOH, much better than that of the commercial Pt/C catalyst. Density functional theory calculations suggest the optimized H sorption kinetics on Mo₂N after P doping, elucidating the superior activity.

在所有pH值下具有高电流密度的高效的氢生成反应（HER）电催化剂对于可持续制氢至关重要。在这里，我们报告一个独立的HER电极，通过一步碳化和原位形成的3维碳纳米片基质（P-Mo ₂ N-CNS）中嵌入的磷掺杂氮化钼纳米颗粒。所制备的催化剂显示具有相互连接的多孔微观结构的独立式结构。平均直径为4.4 nm的P掺杂Mo ₂ N纳米颗粒很好地嵌入3维垂直碳纳米片基质中。在大电流密度下，在碱性，中性和酸性介质中观察到了显着的电催化HER性能。P-Mo的超电势在0.5 MH ₂ SO ₄和1.0 M PBS中驱动100 mA cm ^-2电流密度的₂ N-CNS分别仅为181和221 mV。尤其是，电流密度在1.0 M KOH中的256 mV的低过电势下达到1000 mA cm ^-2，远好于市售Pt / C催化剂。密度泛函理论计算表明，P掺杂后在Mo ₂ N上具有最佳的H吸附动力学，从而阐明了优越的活性。