Selective Electroreduction of CO₂ to Carbon-Rich Products with a Simple Binary Copper Selenide Electrocatalyst

Author

Apurv Saxena
Wipula Liyanage
Jahangir Masud
Shubhender Kapila, Missouri University of Science and TechnologyFollow
Manashi Nath, Missouri University of Science and Technology

Abstract

In this article solvothermally synthesized copper selenide nanostructures have been reported as highly efficient electrocatalysts for carbon dioxide reduction under ambient conditions with high selectivity for carbon-rich C₂ products at a low applied potential. In addition to electrochemical measurements, density functional theory calculations were also performed to investigate the adsorption energy of the key intermediate carbon monoxide on the catalyst surface. The authors proposed that CO adsorption energy on the surface can be a critical component to determine the extent of CO₂ reduction on the surface, whereby a low CO adsorption energy was expected to yield primarily C1 products while a very large adsorption energy leads to catalyst poisoning. In this article the authors have shown that by carefully designing the catalyst surface to optimize the CO adsorption energy and dwell time, selenide based electrocatalysts can indeed show more efficient CO₂ reduction compared to the base metal, leading to carbon-rich products. This is one of the first reports where the Cu₂Se surface has been studied in detail with experimental as well as DFT studies for CO₂ reduction. Interestingly, the reduction products showed dependence on the applied potential forming exclusively formic acid at a high applied potential (1.2 V and higher vs. RHE), while ethanol and acetic acid were produced in high yield at potentials lower than 0.8 V vs. RHE. The applied potential required for CO₂ with copper selenide was as low as 100 mV vs. RHE and is one of the lowest reported to date. The CO₂ reduction products were analyzed through NMR and GC TCD spectroscopy which showed ethanol and acetic acid production in excess of 80% faradaic efficiency at a low applied potential.

Recommended Citation

A. Saxena et al., "Selective Electroreduction of CO₂ to Carbon-Rich Products with a Simple Binary Copper Selenide Electrocatalyst," Journal of Materials Chemistry A, vol. 9, no. 11, pp. 7150 - 7161, Royal Society of Chemistry, Mar 2021.

The definitive version is available at https://doi.org/10.1039/d0ta11518e

Department(s)

Chemistry

International Standard Serial Number (ISSN)

2050-7488

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2021 Royal Society of Chemistry, All rights reserved.

Publication Date

21 Mar 2021