Homogeneous Vacancies-Enhanced Orbital Hybridization for Selective and Efficient CO2-to-CO Electrocatalysis

Yuntong Qin; Guangming Zhan; Cun Tang; Di Yang; Xibo Wang; Jianhua Yang; Chengliang Mao; Zhentian Hao; Shuangyu Wang; Yixin Qin; Hongmei Li; Ke Chen; Min Liu; Jie Li

doi:10.1021/acs.nanolett.3c01905

Homogeneous Vacancies-Enhanced Orbital Hybridization for Selective and Efficient CO₂-to-CO Electrocatalysis

Nano Lett. 2023 Oct 25;23(20):9227-9234. doi: 10.1021/acs.nanolett.3c01905. Epub 2023 Oct 4.

Authors

Yuntong Qin¹, Guangming Zhan², Cun Tang¹, Di Yang¹, Xibo Wang¹, Jianhua Yang³, Chengliang Mao⁴, Zhentian Hao¹, Shuangyu Wang¹, Yixin Qin¹, Hongmei Li⁵, Ke Chen^{1

6}, Min Liu⁵, Jie Li¹

Affiliations

¹ School of Physics and Electronics, International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, Henan University, Kaifeng 475004, China.
² School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
³ Laboratory of Thin Film and Microfabrication (Ministry of Education), Department of Micro/Nano Electronics, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
⁴ Materials Chemistry and Nanochemistry Research Group, Solar Fuels Cluster, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada.
⁵ Hunan Joint International Research Center for Carbon Dioxide Resource Utilization, School of Physics and Electronics, Central South University, Changsha 410083, China.
⁶ School of Future Technology, Henan Key Laboratory of Photovoltaic Materials, Henan University, Kaifeng 475004, China.

PMID: 37791735
DOI: 10.1021/acs.nanolett.3c01905

Abstract

Crafting vacancies offers an efficient route to upgrade the selectivity and productivity of nanomaterials for CO₂ electroreduction. However, defective nanoelectrocatalysts bear catalytically active vacancies mostly on their surface, with the rest of the interior atoms adiaphorous for CO₂-to-product conversion. Herein, taking nanosilver as a prototype, we arouse the catalytic ability of internal atoms by creating homogeneous vacancies realized via electrochemical reconstruction of silver halides. The homogeneous vacancies-rich nanosilver, compared to the surface vacancies-dominated counterpart, features a more positive d-band center to trigger an intensified hybridization of the Ag_d orbital with the C_P orbital of the *COOH intermediate, leading to an accelerated CO₂-to-CO transformation. These structural and electronic merits allow a large-area (9 cm^-2) electrode to generate nearly pure CO with a CO/H₂ Faradaic efficiency ratio of 6932 at an applied current of 7.5 A. These findings highlight the potential of designing new-type defects in realizing the industrialization of electrocatalytic CO₂ reduction.

Keywords: CO electrosynthesis; defect engineering; electrocatalytic CO2 reduction; silver nanomaterials.