MOF-derived copper selenides implanted in octahedral carbon matrix for efficient hydrogen evolution reaction

The development of durable, efficient catalysts is vital in electrochemical water dissociation. Metal-organic frameworks (MOFs) based nanomaterials have been explored due to their well-distribution metal nodes and stability, but the shortage of efficient cathode compounds for electrochemical hydrogen evolving restricted their industrial applications. Herein, Cu₂Se nanocrystals embedded in the octahedral carbon frameworks (Cu₂Se/C) were fabricated using a copper-related MOF template through a one-step selenization technique. Interestingly, the catalytic efficacy of Cu₂Se/C is better than that of Cu/C and Cu-MOF as catalysts for hydrogen generation in an acidic medium. In particular, Cu₂Se/C shows a moderate overpotential of 220 mV at a current density of 10 mA cm⁻² and a low Tafel slope of 54.5 mV dec⁻¹. Also, this catalyst presents outstanding durability with 2000 cycling operations and 12 h of testing by chronoamperometry. The high efficiency is assigned to the synergistic effect of Cu₂Se nanoparticles and carbon frameworks, which play essential roles in increasing exposed catalytic sites and protected active centers. The results may open potential direction to prepare economical hydrogen-evolving electrocatalysts.