Electroreduction of CO 2 to CO over wide potential window by in situ electrodeposited CdCO 3 /Cd-CP electrocatalysts

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Vol. 10; no. 43; pp. 23028 - 23036
• Main Authors: Yang, Jie, Yang, Han, Zhang, Renjie, Zhou, Guangying, Li, Hongping, Yang, Dexin
• Format: Journal Article
• Language: English
• Published: 08.11.2022
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/D2TA06309C

The design of robust electrocatalysts for CO 2 electroreduction with large current density and high selectivity for the desired production is a crucial step in realizing a carbon-neutral energy cycle and producing more valuable chemicals and fuels. Herein, the CdCO 3 /Cd nanostructure was in situ electrodeposited on a carbon paper (CP) substrate to fabricate CdCO 3 /Cd-CP- x (where x represents the concentration of Cd(NO 3 ) 2 ·4H 2 O) electrocatalysts that can boost the electrocatalytic performance of CO 2 electroreduction. When CdCO 3 /Cd-CP-2 was applied as an electrocatalyst, the faradaic efficiency (FE) of CO production remained above 90% over a wide potential window, and the current density reached up to 203 mA cm −2 at −2.4 V vs. Ag/Ag + . The enhanced CO 2 electroreduction was mainly attributed to the intrinsic properties of the CdCO 3 /Cd nanostructure with abundant active sites, the introduction of CdCO 3 , and tight contact with the CP substrate. Density functional theory calculations illustrated that the CdCO 3 in the electrocatalyst promoted the formation of the *COOH intermediate, and the synergistic effect between the CdCO 3 and the Cd support decreased the adsorption ability for the *CO intermediate, which improved the CO production rate. Furthermore, the CdCO 3 /Cd-CP-8 electrocatalyst also exhibited highly selective CO production ability at low CO 2 concentration with outstanding CO 2 conversion rate (34%), which offers a chance to achieve the requirements of practical applications.