High selective electrocatalytic reduction of carbon dioxide to ethylene enabled by regulating the microenvironment over Cu-Ag nanowires

• Published in: Journal of colloid and interface science Vol. 662; pp. 786 - 795
• Main Authors: Fan, Dehe, Zhang, Shiji, Li, Yumeng, Bin, Hua, Li, Ruopeng, Li, Yaqiang, An, Maozhong, Yang, Peixia, Zhang, Jinqiu
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 15.05.2024
• Subjects: Electrochemical CO2 reduction; Ethylene; Local pH; Nanowire catalyst; Tandem catalysis; Electrochemical CO2 reduction; Local pH; Nanowire catalyst; Tandem catalysis; Ethylene; Electrochemical CO reduction
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2024.02.028

[Display omitted] Copper-based tandem catalysts are effective candidates for yielding multi-carbon (C2+) products in electrochemical reduction of carbon dioxide (CO2RR). However, these catalysts still face a significant challenge regarding in the low selectivity for the production of a specific product. In this study, we report a high selectivity of 77.8 %±2 % at −1.0 V (vs RHE) for the production of C2H4 by using a Cu88Ag12NW catalyst which is primarily prepared through a combined Cu-Ag co-deposition and wet chemical method, employing an attractive strategy focused on regulating the microenvironment over Cu-Ag nanowires. The experimental and computational studies show that the higher *CO coverage and lower intermediate adsorption energy are important reasons for achieving the high C2H4 selectivity of Cu88Ag12NW catalyst. Comsol simulation results indicate that dense nanowires exhibit a nano-limiting effect on OH− ions, thereby leading to an increase in local pH and promoting coupling reactions. The catalyst demonstrates no noticeable decrease in current density or selectivity even after 12 h of continuous operation. The Cu-Ag nanowire composite exhibits remarkable catalytic activity, superior faradaic efficiency, excellent stability, and easy synthesis, which highlights its significant potential for electro-reducing carbon dioxide into valuable products.