CoSe2 nanoparticles embedded MOF-derived Co-N-C nanoflake arrays as efficient and stable electrocatalyst for hydrogen evolution reaction

Abstract

It is still challenging to develop highly efficient and stable non-noble metal-based electrocatalysts for hydrogen evolution reaction (HER). Herein, CoSe2 nanoparticles embedded Co-N-doped carbon nanoflake arrays (CS@CNC NAs) are grown on carbon cloth (CC) through a co-precipitation and annealing process. The CS@CNC NAs/CC hybrid electrocatalyst shows superior HER performance with a small Tafel slope of 38 mV dec−1, an ultralow overpotential of 84 mV at 10 mA cm-2 and an excellent long-term stability with nearly no decay even after 72 h. The outstanding HER performance of CS@CNC NAs/CC is mainly attributed to the synergetic effects of CoSe2 nanoparticles and CNC nanoflake arrays, which can not only provide rich active sites, easy access of electrolyte and diffusion of H2 bubbles, but also guarantee its high conductivity and structural stability. This work provides a novel strategy for the rational fabrication of highly effective and stable transition metal selenide-based electrocatalysts for HER.