Modulation of the Coordination Environment of Copper for Stable CO₂ Electroreduction with Tunable Selectivity

Manipulating the product selectivity of an electrochemicalCO(2) reduction reaction (CO2RR) is challengingdueto the unclear and uncontrollable active sites. Here, we report stableCO(2)RR operation with tunable product selectivity over afamily of molecule-modulated copper catalysts. The coordination environmentof Cu in catalysts is modulated by an imidazole-based molecule viadifferent synthetic routes. Various carbonaceous products rangingfrom carbon monoxide, methane, and ethylene were selectively producedvia, respectively, tuning the coordination environment of copper atomsfrom Cu-N, Cu-C, and Cu-Cu. Density functionaltheory (DFT) calculations reveal that the Cu-N sites weakenthe adsorption energy of the *CO intermediate, which is beneficialfor CO desorption. The Cu-C and Cu-Cu sites, respectively,facilitate the formation of *OCOH and *-(CO)(2) intermediates,favoring the CH4 and C2H4 pathways.This work provides a stable and simple model system for studying theinfluence of coordination elements on the product selectivity of CO2RR.