Cobalt doped β-molybdenum carbide nanoparticles encapsulated within nitrogen-doped carbon for oxygen evolution

Abstract

Herein, we report a novel cobalt doped transition metal carbide-based OER electrocatalyst, cobalt doped β-molybdenum carbide (β-Mo₂C) encapsulated by a nitrogen doped carbon framework, Co_0.1-β-Mo₂C@NC, which shows an unexpected onset overpotential of 200 mV and an overpotential of 262.2 mV at a current density of 10 mA cm⁻². This strategy of cobalt doping reduces the amount of cobalt, and increases the density of active sites as well; furthermore, the introduction of molybdenum carbide enhances the stability of the catalyst.