CO₂ Electroreduction to C₂₊ Products over Cu-Pb Heterojunction Catalyst

The electrochemical CO₂ reduction reaction (CO₂RR) presents a promising approach for producing valuable chemicals and fuels, offering a dual benefit in terms of environmental preservation and the efficient utilization of carbon resources. In this work, we proposed a stepwise electrodeposition method to prepare Cu−Pb bimetallic heterojunction catalyst on polyaniline-modified carbon paper (PANI-CuPb-x), where x is the electrodeposition times(min). Among the studied catalysts, the electrode electrodeposited for 2 min (PANI-CuPb-2) exhibited a remarkable performance during the electrocatalysis CO₂ to multicarbon (C₂₊) products process, achieving a Faraday efficiency (FE) of 81.46 % and a partial current density of 15.41 mA cm⁻² at −1.2 V (vs. RHE) in an H-type cell. The detailed study demonstrated that introducing Pb could effectively improve the formation of COOH*inhibit hydrogen evolution reaction (HER). Furthermore, the heterojunction structure in the catalysts facilitated C−C coupling of the generated C1 intermediate species, which enhanced the CO₂ to C₂₊ reaction.