The Effect of Mo Addition on Electrocatalytic Activity and Stability of Fe-Co-P-C Metallic Glasses for Hydrogen Evolution

Transition metals and alloys are expected to act as electrocatalysts for water splitting. Herein, we designed novel Fe-based metallic glasses by tuning the amount of Mo alloying. The prepared Mo-alloyed glassy ribbons substantially improved electrocatalytic activity for hydrogen evolution, with the optimal sample having an over-potential of 90 mV at a current density of 10 mA cm(-2) in an acidic solution. The Mo-alloyed glasses presented here are the most efficient electrocatalysts to date among all known non-noble metallic glasses. In addition, we discovered that the Mo-dependent electrocatalytic activity of the studied alloys correlated closely with their glass-forming ability. Therefore, the superior electrocatalytic properties and high glass-forming ability of the present glasses are presumed to simultaneously originate from the intrinsic amorphous structure induced by tuning the Mo content. The results not only demonstrate the excellent electrocatalytic properties of Mo-alloyed metallic glasses as low-cost electrocatalysts for practical use, but also provide new mechanistic evidence for the electrocatalytic activity of amorphous metals.