Altering the CO Electroreduction Pathways Towards C or C Products via Engineering the Strength of Interfacial Cu-O Bond.

Copper (Cu)-based catalysts have established their unique capability for yielding wide value-added products from CO. Herein, we demonstrate that the pathways of the electrocatalytic CO reduction reaction (CORR) can be rationally altered toward C or C products by simply optimizing the coordination of Cu with O-containing organic species (squaric acid (HCO) and cyclohexanehexaone (CO)). It is revealed that the strength of Cu-O bonds can significantly affect the morphologies and electronic structures of derived Cu catalysts, resulting in the distinct behaviors during CORR. Specifically, the CO-Cu catalysts made up from organized nanodomains shows a dominant C pathway with a total Faradaic efficiency (FE) of 63.7 % at -0.6 V (versus reversible hydrogen electrode, RHE). In comparison, the CO-Cu with an about perfect crystalline structure results in uniformly dispersed Cu-atoms, showing a notable FE of 65.8 % for C products with enhanced capability of C-C coupling. The latter system also shows stable operation over at least 10 h with a high current density of 205.1 mA cm at -1.0 V, i.e., is already at the boarder of practical relevance. This study sheds light on the rational design of Cu-based catalysts for directing the CORR reaction pathway.