Janus Structured AgCu Nanoparticles on Nitrogen Doped Graphene Oxide for Selective CO2 Reduction to Acetic Acid

We report a phase-separated AgCu supported on nitrogen-doped reduced graphene oxide (NrGO) catalyst that enables the selective electrochemical reduction of CO2 to acetic acid under mild conditions. The NrGO support improving hydrophobicity, suppresses the hydrogen evolution reaction, and enhances interfacial electron transfer, contributing to the overall catalytic efficiency and stability. The AgCu nanoparticles were synthesized via a hot soap method and uniformly anchored onto NrGO sheets, followed by annealing to induce spatially distinct AgCu domains. This unique morphology facilitates CO spillover from Ag to Cu sites, enhancing C–C coupling and promoting acetic acid formation. At −1.6 V vs Ag/AgCl, the 30 mol % AgCu catalyst achieved a Faradaic efficiency of 32% for acetic acid, the highest among all tested compositions. Structural and electrochemical analyses reveals that this interfacial structure enables effective intermediate control and enhances stability, compared to conventional alloy-type AgCu catalysts. These findings provide a promising strategy for CO2 valorization using earth-abundant materials.