Plasma-engineered Mo2C catalysts for high-activity hydrogen evolution reaction

As a typical hard alloy, Mo2C attracted most researchers' interests for excellent mechanical stability, which reveals great potentials as robust electrocatalysts. However, the deviation of Mo2C catalytic adsorption and desorption energy from the volcano curve center hinders its catalytic efficiency, and the robust lattice structure of Mo2C poses a significant challenge to conventional modification approaches aimed at improving its catalytic properties. In current study, Ar plasma etched Mo2C nanofibers (Ar-Mo2C) were successfully fabricated which exhibits significantly higher HER activity with an overpotential of 151 mV and a Tafel slope of 29 mV dec  1. Ar etching can create Mo and C vacancies to enhance the charge transfer capability. Current work paves an efficient way for surface processing of hard alloys for high electrocatalytic activity, which inspires future robust nano-electrocatalysts design.