A Sn-stabilized Cu δ+ electrocatalyst toward highly selective CO2-to-CO in a wide potential range

Xingxing Tan; Weiwei Guo; Shoujie Liu; Shunhan Jia; Liang Xu; Jiaqi Feng; Xupeng Yan; Chunjun Chen; Qinggong Zhu; Xiaofu Sun; Buxing Han

doi:10.1039/d2sc04607e

A Sn-stabilized Cu ^δ+ electrocatalyst toward highly selective CO₂-to-CO in a wide potential range

Chem Sci. 2022 Sep 26;13(40):11918-11925. doi: 10.1039/d2sc04607e. eCollection 2022 Oct 19.

Authors

Xingxing Tan^{1

2}, Weiwei Guo^{1

2

3}, Shoujie Liu⁴, Shunhan Jia^{1

2}, Liang Xu¹, Jiaqi Feng¹, Xupeng Yan^{1

2}, Chunjun Chen¹, Qinggong Zhu¹, Xiaofu Sun^{1

2}, Buxing Han^{1

2

5}

Affiliations

¹ Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid and Interface and Thermodynamics, CAS Research/ Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences Beijing 100190 P. R. China sunxiaofu@iccas.ac.cn hanbx@iccas.ac.cn.
² School of Chemical Sciences, University of Chinese Academy of Sciences Beijing 100049 P. R. China.
³ College of Chemistry and Chemical Engineering, Qingdao University Qingdao 266071 P. R. China.
⁴ Chemistry and Chemical Engineering of Guangdong Laboratory Shantou 515063 P. R. China.
⁵ Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University Shanghai 200062 P. R. China.

Abstract

Current techno-economic evaluation manifests that the electrochemical CO₂ reduction reaction (eCO₂RR) to CO is very promising considering its simple two-electron transfer process, minimum cost of electricity, and low separation cost. Herein, we report a Sn-modification strategy that can tune the local electronic structure of Cu with an appropriate valence. The as-prepared catalysts can alter the broad product distribution of Cu-based eCO₂RR to predominantly generate CO. CO faradaic efficiency (FE) remained above 96% in the wide potential range of -0.5 to -0.9 V vs. the reversible hydrogen electrode (RHE) with CO partial current density up to 265 mA cm^-2. The catalyst also had remarkable stability. Operando experiments and density functional theory calculations demonstrated that the surface Cu ^δ+ sites could be modulated and stabilized after introducing Sn. The Cu ^δ+ sites with low positive valence were conducive to regulating the binding energy of intermediates and resulted in high CO selectivity and maintained the stability of the catalyst. Additionally, scaling up the catalyst into a membrane electrode assemble system (MEA) could achieve a high overall current of 1.3 A with exclusive and stable CO generation.