Single atom copper anchored N-doped graphene-like carbon for CO₂ electroreduction

Carbon-based materials are widely used as electrocatalysts for the CO₂ reduction reaction (CO₂RR) due to their high conductivity and large surface area. Recent studies highlighted that the presence of Cu in trace amounts over the graphene-based electrocatalyst significantly affects their electrochemical properties. Cu is particularly selective for forming hydrocarbons, and multi-carbon oxygenates at high efficiencies, unlike most electrocatalysts, primarily producing C₁ products. Despite this, current electrocatalysts exhibit limited selectivity toward C₂ products. In this study, the nitrogen-doped graphene-like framework was synthesised, and the effect of introducing trace levels of single-atom Cu (Cu@NG) on CO₂RR was studied. DFT analysis was further performed to understand the mechanism involved during electrocatalysis, and the results were well aligned with the experimental data. The results confirm that the co-presence of graphitic-N and Cu single atoms in Cu@NG serves as the primary active species for CO₂RR. The electrocatalyst demonstrated excellent performance, achieving a faradaic efficiency (FE) of 91.0% at -0.8 V versus RHE, with a 59% FE specifically for C₂H₄ production. This highlights the potential of Cu@NG for selective CO₂RR toward multi-carbon products.