In situ formation of N-doped carbon-coated porous MoP nanowires: a highly efficient electrocatalyst for hydrogen evolution reaction in a wide pH range

Molybdenum phosphide (MoP) is a promising non-noble-metal electrocatalyst for hydrogen evolution reaction (HER), but coordination of high HER activity and fast HER kinetics is a challenge. Herein, we proposed a highly efficient HER electrocatalyst composed of N-doped carbon-coated porous MoP nanowires (MoP@NC) by phosphorization of organic-inorganic Mo₃O₁₀(C₆H₈N)₂·2H₂O NWs. The MoP@NC with mesopores MoP framework and micropores N-doped carbon-coating facilitates the electrolyte/bubbles diffusion and ion/electron transport, owns abundant active sites and smaller adsorption free energy of H (ΔG_H*) at the interface boosting the HER performance. Small overpotentials (η₁₀) of 96, 191 and 149 mV with Tafel slopes of 49.2, 95.0 and 61.7 mV dec⁻¹ in acidic, neutural and alkaline solutions were achieved as well as excellent stability, which is better than that of bare MoP NWs and other MoP-based electocatalysts. The results reveal a simple and effective approach to produce inexpensive electrocatalysts with excellent HER properties in a wide pH range.