Copper-based pyridine complex catalyst for enhanced C2+ selectivity of CO2 Electroreduction

Abstract

Electrochemical carbon dioxide reduction reaction (ECO2RR) is one of the methods taking CO2 into value-added chemicals, prohibiting global warming. Cu-based catalysts are widespread employed for ECO2RR because of its inexpensive price, although they display low selectivity of C2+ due to hydrogen evolution reaction (HER). Accordingly, we take advantage of Cu2+ coordination with pyridine and pyridine derivatives synthesizing CuL2Cl2 (L=pyridine, 4-PP, 4-BP), increasing the CO2 adsorption sites to selective HER suppression, achieving FEC2+ of 55% the at the voltage of -1.6 V vs. RHE in a flow cell while the FEH2 lowers to 18%. And the analyses reveal the features of CO2 adsorption by XPS that new appearing bands verifying pyridyl and phenyl can provide extra adsorption sites. And electroreduction process is monitored by In-situ FTIR, with *COOH, *OCCOH et al. intermediates observed, disclosing the possible reaction path. This research provides a new mentality in the catalyst area.