Understanding the Role of Functional Groups in Polymeric Binder for Electrochemical Carbon Dioxide Reduction on Gold Nanoparticles

Abstract Electrochemical CO 2 reduction reaction (CO 2 RR) is one of the promising strategies for converting CO 2 to value‐added chemicals. Gold (Au) catalysts are considered to be the best benchmarking materials for CO 2 RR to produce CO. In this work, the role of different functional groups of polymeric binders on CO 2 RR over Au catalysts is systematically investigated by combined experimental measurements and density functional theory (DFT) calculations. Especially, it is revealed that the functional groups can play a role in suppressing the undesired hydrogen evolution reaction, the main competing reaction against CO 2 RR, thus enabling more catalytic active sites to be available for CO 2 RR and enhancing the CO 2 RR activity. Consistent with the DFT prediction, fluorine (F)‐containing functional groups in the F‐rich polytetrafluoroethylene binder lead to a high Faradaic efficiency (≈94.7%) of CO production. This study suggests a new strategy by optimizing polymeric binders for the selective CO 2 RR.