Activating COOH* intermediate by Ni/Ni3ZnC0.7 heterostructure in porous N-doped carbon nanofibers for boosting CO2 electroreduction

Electrochemical reduction of CO2 (CO2RR) to value-added chemicals is a feasible strategy to build a carbon neutral society and store energy. However, the sluggish kinetics of CO2RR accompanied by competing hydrogen evolution reaction (HER) makes the practical application of this process very challenging. Herein, we construct a Ni/Ni3ZnC0.7 heterostructured catalyst wrapped in porous N-doped carbon nanofibers via a facile electrospinning strategy for CO2RR. Remarkably, the as-prepared Ni/Ni3ZnC0.7 catalyst exhibits a high selectivity of 91.5% toward CO, a superior CO partial current density of 11 mA cm−2 at −0.8 V versus the reversible hydrogen electrode (vs. RHE) and maintaining 93.4% of its initial selectivity after 45 h of continuous electrolysis. The calculation results of density functional theory (DFT) show that the heterostructure of Ni/Ni3ZnC0.7 catalyst is beneficial to the formation of *COOH and enhances the efficiency of electrocatalytic CO2 conversion.