Interface engineering of Mo8/Cu heterostructures toward highly selective electrochemical reduction of carbon dioxide into acetate

Electrocatalytic CO2 reduction reaction (CO2RR) is a promising pathway for storage of renewable electricity and converting CO2 into value-added products. It`s highly desired to obtain acetic acid via CO2RR since it`s an important chemical feedstock and high energy-density liquid fuel. However, developing highly efficient electrocatalysts for selective CO2RR toward acetate remains formidable challenge. We report an interface engineering strategy to modify copper nanocubes with polyoxometalate (POM) to generate Cu–O–Mo interface as active sites for CO2RR, achieving state-of-the-art activity with 48.68% acetate formation Faradaic efficiency and current density of ∼110 mA cm−2 at -1.13 V vs RHE. DFT calculations suggest the interface of Cu planes and polyoxometalate clusters with abundant Cu–O–Mo active sites promote the generation of *CH3 and successive coupling with CO2 insertion, showing a potential dependence of acetate production. This work provides a Cu–O–Mo interface model for the rational design of earth-abundant metal based electrocatalysts for CO2RR and other renewable energy conversions.