Wet-chemistry synthesis of cobalt carbide nanoparticles as highly active and stable electrocatalyst for hydrogen evolution reaction

Transition metal carbide (TMC) nanomaterials are promising alternatives to Pt, and are widely used as heterogeneous electrocatalysts for the electrochemical hydrogen evolution reaction (HER). In this work, a bromide-induced wet-chemistry strategy to synthesize Co₂C nanoparticles (NPs) was developed. Such NPs exhibited high electrocatalytic activity (η = 181 mV for j = −10 mA·cm⁻²) and long-term stability (no obvious performance decrease after 4,000 cycles) for the HER. This study will pave the way for the design and fabrication of TMC NPs via a wet-chemistry method, and will have significant impacts on broader areas such as nanocatalysis and energy conversion. [Figure not available: see fulltext.]