Covalent organic framework derived Mo2C-MoNi4 chainmail catalysts for hydrogen evolution

Abstract

Mo-based materials have been explored as promising non-precious metal catalysts for hydrogen evolution reactions (HER); however, their long-term stability under strong acidic and alkaline electrolytes to meet industrial requirements is still a remaining challenge. Herein, we described a methodology for fabricating a stable Mo-based HER chainmail catalyst, which is derived from pyrolysis of Mo, Ni adsorbed two-dimensional covalent orgainnic framework (COF). The derived chainmail catalyst shows an in-situ formed Mo2C-MoNi4 structure embedded in nitrogen-doped carbon (Mo2C-MoNi4@NC), which shows excellent activities for HER with a small overpotential of 104 mV to deliver 10 mA cm−2. Most importantly, with the protective effect of the nitrogen-doped graphene shell layer, the Mo2C-MoNi4@NC chainmail catalyst maintained remarkable stability after chronopotentiometry testing even for 140, 000 s both in acidic and alkaline media, proving its excellent durability. This work sheds new light on designing stable non-noble-metal-based catalysts for wide applications in energy conversion.