Enhanced Ethylene Formation from Carbon Dioxide Reduction through Sequential Catalysis on Au Decorated Cubic Cu 2 O Electrocatalyst

• Published in: European journal of inorganic chemistry Vol. 2021; no. 24; pp. 2353 - 2364
• Main Authors: Cao, Xuerui, Cao, Guangwei, Li, Mei, Zhu, Xinli, Han, Jinyu, Ge, Qingfeng, Wang, Hua
• Format: Journal Article
• Language: English
• Published: 25-06-2021
• ISSN: 1434-1948; 1099-0682
• DOI: 10.1002/ejic.202100229

Abstract
Electrochemical reduction of carbon dioxide to fuels has been recognized as a perspective way to address the environmental and energy issues. Herein, the novel Au decorated Cu
2
O electrocatalysts were synthesized via the galvanic replacement reaction and the successive pre‐reduction by linear voltammetry (LSV) method. In contrast to Cu
2
O, CO formation became dominant over HCOOH and H
2
on Au
x
Cu
2
O, and a remarkably enhanced selectivity of C
2
H
4
was obtained beyond −1.1 V vs. RHE. Among them, Au
0.02
Cu
2
O exhibited the highest Faraday efficiency (FE) of C
2
H
4
of 24.4 % at −1.3 V vs. RHE, which was as high as 2∼2.5 and 5 times of those on other two Au
x
Cu
2
O and bare Cu
2
O, respectively. Meanwhile, it is demonstrated that the optimal ratio of Au/Cu was essential for effective sequential catalysis between Au and Cu
2
O to enhance C−C coupling. Furthermore, the effect of copper states resulting from different pre‐reduction methods on the selectivity of C
2
H
4
was explored. A half decrease of C
2
H
4
FE was observed on HPR‐Au
0.02
Cu
2
O (high potential reduced) relative to the LSV reduced Au
0.02
Cu
2
O, which was ascribed to the different content of Cu
0
and residual Cu
+
in two catalysts. Our results demonstrate an effective approach to construct Cu
2
O based bimetallic catalysts for ethylene formation from CO
2
.