(111) Facet-oriented Cu2Mg Intermetallic Compound with Cu3-Mg Sites for CO2 Electroreduction to Ethanol with Industrial Current Density

Chen Peng; Jiaxing Ma; Gan Luo; Shuai Yan; Junbo Zhang; Yangshen Chen; Ning Chen; Zhiqiang Wang; Wei Wei; Tsun-Kong Sham; Yao Zheng; Min Kuang; Gengfeng Zheng

doi:10.1002/anie.202316907

(111) Facet-oriented Cu₂Mg Intermetallic Compound with Cu₃-Mg Sites for CO₂ Electroreduction to Ethanol with Industrial Current Density

Angew Chem Int Ed Engl. 2024 Apr 22;63(17):e202316907. doi: 10.1002/anie.202316907. Epub 2024 Mar 18.

Authors

Chen Peng^{1

2}, Jiaxing Ma¹, Gan Luo³, Shuai Yan¹, Junbo Zhang¹, Yangshen Chen¹, Ning Chen⁴, Zhiqiang Wang⁵, Wei Wei³, Tsun-Kong Sham⁵, Yao Zheng², Min Kuang⁶, Gengfeng Zheng¹

Affiliations

¹ Laboratory of Advanced Materials, Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, 200438, China.
² School of Chemical Engineering, The University of Adelaide, Adelaide, SA, 5005, Australia.
³ Henan Engineering Center of New Energy Battery Materials, Henan D&A Engineering Center of Advanced Battery Materials, College of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu, 476000, China.
⁴ Canadian Light Source Inc., University of Saskatchewan, Saskatoon, SK, S7 N 2 V3, Canada.
⁵ Department of Chemistry, University of Western Ontario, London, ON, N6 A 5B7, Canada.
⁶ State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, China.

PMID: 38436539
DOI: 10.1002/anie.202316907

Abstract

The efficient ethanol electrosynthesis from CO₂ is challenging with low selectivity at high CO₂ electrolysis rates, due to the competition with H₂ and other reduction products. Copper-based bimetallic electrocatalysts are potential candidates for the CO₂-to-ethanol conversion, but the secondary metal has mainly been focused on active components (such as Ag, Sn) for CO₂ electroreduction, which also promote selectivity of ethylene or other reduction products rather than ethanol. Limited attention has been given to alkali-earth metals due to their inherently active chemical property. Herein, we rationally synthesized a (111) facet-oriented nano Cu₂Mg (designated as Cu₂Mg(111)) intermetallic compound with high-density ordered Cu₃-Mg sites. The in situ Raman spectroscopy and density function theory calculations revealed that the Cu₃ ^- $_{^{δ}}$ ^--Mg^- $_{^{δ}}$ ⁺ active sites allowed to increase *CO surface coverage, decrease reaction energy for *CO-CO coupling, and stabilize *CHCHOH intermediates, thus promoting the ethanol formation pathway. The Cu₂Mg(111) catalyst exhibited a high FE_C2H5OH of 76.2±4.8 % at 600 mA⋅cm^-2, and a peak value of |j_C2H5OH| of 720±34 mA⋅cm^-2, almost 4 times of that using conventional Cu₂Mg with (311) facets, comparable to the best reported values for the CO₂-to-ethanol electroreduction.

Keywords: (111) facets; CO2 electroreduction; Cu2Mg intermetallic compound; alkali-earth metal; electron localization.

Abstract

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