LAUSR

Abstract To explore high-efficiency, 1ow-cost and durable non-precious metal electrocatalysts for hydrogen evolution reaction (HER) in alkaline media, the binder free molybdenum carbide@ nickel foam (Mo2C@NF-x, x represents the calcination temperature) electrodes were synthesized by the hydrothermal and calcination process. Using glucose as the carbon source for the fabrication of Mo2C is not only environmental friendly but also promotes the formation of nanospheres and improves the dispersibility of the catalysts. The carbon shell formed by calcination also can improve the electron transfer between Ni foam substrate and nanospheres. Furthermore, the carbon shell can act as “armour for catalyst”, protecting the Mo2C from the harsh conditions (e.g., strong acidity or alkalinity) and improving the stability of the catalysts during electrocatalysis. The optimal electrocatalyst is Mo2C@NF-850, which only needs overpotential of 42 mV for hydrogen evolution reaction to reach 10 mA cm−2, a small Tafel slope of 76 mV·dec−1, as well as satisfactory durability in 1.0 M KOH electrolyte for HER.