Abstract
The direct electrosynthesis of value-added esters from carbon monoxide (CO) represents a promising strategy for sustainable carbon utilization. In this study, we report the synthesis of propyl acetate with a faradaic efficiency of 16.5% and a partial current density reaching up to 24.7 mA cm(-2) via CO electrolysis on a polarized Cu/Cu(3)N interface. Comprehensive mechanistic investigations elucidate a dual-pathway mechanism: ketene undergoes nucleophilic addition with n-propanol; and C(2)-C(3) coupling occurs between nucleophilic *CH(2)CO and electrophilic intermediates such as *COHCOCO. Charge redistribution and interfacial polarization induced by the Cu/Cu(3)N interface reduce the activation barrier for the electrophilic addition between C(2)-C(3) intermediates. These findings offer an alternative and sustainable pathway for the synthesis of esters through direct CO electroreduction.