Charge-ordered Cu+/Cu2+ pair regulated highly-selective electroreduction of carbon monoxide to acetate

Selective electrochemical reduction of CO2/CO to high-valuable C2+ products is of great importance to alleviate the global warming and energy crisis problems, while the selective production of C2 is severely limited by the CC coupling pathway on the catalyst interface. Herein, by employing a Cu+/Cu2+ charge-ordered metal-organic framework (MOF) material (denoted to be Cu4BHT) as a CO electroreduction catalyst, a high acetate selectivity of 50.3% at 0.7 V versus reversible hydrogen electrode (RHE) has been achieved. An in-depth mechanism study reveals that the charge-ordered Cu+/Cu2+ pair on Cu4BHT interface favors the CO bond activation, CC coupling, and proton-coupled electron transfer dynamics, which results in the selective formation of C2+ products. This work illustrates the critical role of employing charge-ordered Cu+/Cu2+ catalytic site pair for CC coupling, which paves the way for designing highly selective catalysts to promote the formation of the C2 products.