Electrochemical Reduction of CO2 to HCOOH over Copper Catalysts

Weibo Hu; Jiejie Li; Lushan Ma; Wanyu Su; Yanping Zhu; Wenhao Li; Yubin Chen; Liangliang Zou; Zhiqing Zou; Bo Yang; Ke Wen; Hui Yang

doi:10.1021/acsami.1c18902

Electrochemical Reduction of CO₂ to HCOOH over Copper Catalysts

ACS Appl Mater Interfaces. 2021 Dec 8;13(48):57462-57469. doi: 10.1021/acsami.1c18902. Epub 2021 Nov 29.

Authors

Weibo Hu^{1

2

3}, Jiejie Li⁴, Lushan Ma^{1

2}, Wanyu Su^{1

5}, Yanping Zhu^{1

2}, Wenhao Li^{1

4}, Yubin Chen^{1

2}, Liangliang Zou¹, Zhiqing Zou¹, Bo Yang⁴, Ke Wen^{1

4}, Hui Yang^{1

3}

Affiliations

¹ Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China.
² University of Chinese Academy of Sciences, Beijing 100039, China.
³ Dalian National Laboratory for Clean Energy, Chinese Academy of Sciences, Dalian 116023, China.
⁴ School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China.
⁵ Department of Chemistry, Shanghai University, Shanghai 201210, China.

PMID: 34843201
DOI: 10.1021/acsami.1c18902

Abstract

Although great progress has been made in the field of electrochemical CO₂ reduction reaction (eCO₂RR), inducing product selectivity is still difficult. We herein report that a thiocyanate ion (SCN^-) switched the product selectivity of copper catalysts for eCO₂RR in an H-cell. A cuprous thiocyanate-derived Cu catalyst was found to exhibit excellent HCOOH selectivity (faradaic efficiency = 70-88%) over a wide potential range (-0.66 to -0.95 V vs RHE). Furthermore, it was revealed that the formation of CO and C₂H₄ over commercial copper electrodes could be dramatically suppressed with the presence of SCN^-, switching to HCOOH. Density functional theory calculations disclosed that SCN^- made the formation of HCOO* easier than COOH* on Cu (211), facilitating the HCOOH generation. Our results provide a new insight into eCO₂RR and will be helpful in the development of cheap electrocatalysts for specific utilization.

Keywords: HCOOH; anion effect; electrochemical CO2 reduction reaction; reaction pathway; thiocyanate.