Facile construction of porous and heterostructured molybdenum nitride/carbide nanobelt arrays for large current hydrogen evolution reaction

The development of cost-effective, highly efficient and stable electrocatalysts for alkaline water electrolysis at a large current density has attracted considerable attention. Herein, we reported a one-dimensional (1D) porous Mo2C/Mo2N heterostructured electrocatalyst on carbon cloth as robust electrode for large current hydrogen evolution reaction (HER). The MoO3 nanobelt arrays and urea were used as the metal and non-metal sources to fabricate the electrocatalyst by one-step thermal reaction. Due to the in-situ formed abundant high active interfaces and porous structure, the Mo2C/Mo2N electrocatalyst shows enhanced HER activity and kinetics, as exemplified by low overpotentials of 54, 73, and 96 mV at a current density of 10 mA cm−2 and small Tafel slopes of 48, 59 and 60 mV dec−1 in alkaline, neutral and acid media, respectively. Furthermore, the optimal Mo2C/Mo2N catalyst only requires a low overpotential of 290 mV to reach a large current density of 500 mA cm−2 in alkaline media, which is superior to commercial Pt/C catalyst (368 mV) and better than those of recently reported Mo-based electrocatalysts. This work paves a facile strategy to construct highly efficient and low-cost electrocatalyst for water splitting, which could be extended to fabricate other heterostructured electrocatalyst for electrocatalysis and energy conversion.