TY - JOUR
T1 - Cu-Ag interactions in bimetallic Cu-Ag catalysts enhance C2+ product formation during electrochemical CO reduction
AU - Rollier, Floriane A.
AU - Muravev, Valery
AU - Kosinov, Nikolay
AU - Wissink, Tim
AU - Anastasiadou, Dimitra
AU - Ligt, Bianca
AU - Barthe, Laurent
AU - Costa Figueiredo, Marta
AU - Hensen, Emiel J.M.
N1 - Publisher Copyright:
© 2025 The Royal Society of Chemistry.
PY - 2025/1/21
Y1 - 2025/1/21
N2 - The electroreduction of CO (CORR) is a promising alternative to the direct CO
2 electroreduction reaction (CO2RR) to produce C
2+ products. Cu-based electrocatalysts enable the formation of C–C bonds, leading to various C
2+ hydrocarbon and oxygenate products. Herein, we investigated how the composition of bimetallic Cu–Ag catalysts impacted the nature of the Cu–Ag interactions and the product distribution of the CORR, aiming to improve the selectivity to C
2+ products. Cu–Ag catalysts containing 1–50 mol% Ag were prepared by sol–gel synthesis. A Ag content of 10 mol% of Ag (Cu
0.9Ag
0.1) was optimum with respect to increasing the C
2+ product selectivity and suppressing H
2 evolution. Operando X-ray absorption spectroscopy and quasi-in situ X-ray photoelectron spectroscopy demonstrated the complete reduction of CuO to Cu during CORR. Electron microscopy (EM) and in situ wide-angle X-ray scattering (WAXS) revealed substantial restructuring during reduction. EM imaging showed the formation of Ag–Cu core–shell structures in Cu
0.9Ag
0.1, while separate Cu and Ag particles were predominant at higher Ag content. In situ WAXS revealed the formation of a Cu–Ag nanoalloy phase in the bimetallic Cu–Ag samples. The optimum Cu
0.9Ag
0.1 sample contained more Cu–Ag nanoalloys than samples with a higher Ag content. The Cu–Ag interfaces between the Ag-core and the Cu-shell in the bimetallic particles are thought to host the nanoalloys. The optimum CORR performance for Cu
0.9Ag
0.1 is likely due to the enhanced Cu–Ag interactions, as confirmed by a sample prepared with the same surface composition by galvanic exchange.
AB - The electroreduction of CO (CORR) is a promising alternative to the direct CO
2 electroreduction reaction (CO2RR) to produce C
2+ products. Cu-based electrocatalysts enable the formation of C–C bonds, leading to various C
2+ hydrocarbon and oxygenate products. Herein, we investigated how the composition of bimetallic Cu–Ag catalysts impacted the nature of the Cu–Ag interactions and the product distribution of the CORR, aiming to improve the selectivity to C
2+ products. Cu–Ag catalysts containing 1–50 mol% Ag were prepared by sol–gel synthesis. A Ag content of 10 mol% of Ag (Cu
0.9Ag
0.1) was optimum with respect to increasing the C
2+ product selectivity and suppressing H
2 evolution. Operando X-ray absorption spectroscopy and quasi-in situ X-ray photoelectron spectroscopy demonstrated the complete reduction of CuO to Cu during CORR. Electron microscopy (EM) and in situ wide-angle X-ray scattering (WAXS) revealed substantial restructuring during reduction. EM imaging showed the formation of Ag–Cu core–shell structures in Cu
0.9Ag
0.1, while separate Cu and Ag particles were predominant at higher Ag content. In situ WAXS revealed the formation of a Cu–Ag nanoalloy phase in the bimetallic Cu–Ag samples. The optimum Cu
0.9Ag
0.1 sample contained more Cu–Ag nanoalloys than samples with a higher Ag content. The Cu–Ag interfaces between the Ag-core and the Cu-shell in the bimetallic particles are thought to host the nanoalloys. The optimum CORR performance for Cu
0.9Ag
0.1 is likely due to the enhanced Cu–Ag interactions, as confirmed by a sample prepared with the same surface composition by galvanic exchange.
UR - http://www.scopus.com/inward/record.url?scp=85212318163&partnerID=8YFLogxK
U2 - 10.1039/d4ta04263h
DO - 10.1039/d4ta04263h
M3 - Article
C2 - 39679096
AN - SCOPUS:85212318163
SN - 2050-7488
VL - 13
SP - 2285
EP - 2300
JO - Journal of Materials Chemistry A
JF - Journal of Materials Chemistry A
IS - 3
ER -