TY - JOUR
T1 - Effect of Halide Anions on Electrochemical CO2 Reduction in Non-Aqueous Choline Solutions using Ag and Au Electrodes
AU - Farahmandazad, Hengameh
AU - Asperti, Simone
AU - Kortlever, Ruud
AU - Goetheer, Earl
AU - de Jong, Wiebren
PY - 2024
Y1 - 2024
N2 - In this study, the effect of halide anions on the selectivity of the CO2 reduction reaction to CO was investigated in choline-based ethylene glycol solutions containing different halides (ChCl : EG, ChBr : EG, ChI : EG). The CO2RR was studied using silver (Ag) and gold (Au) electrodes in a compact H-cell. Our findings reveal that chloride effectively suppresses the hydrogen evolution reaction and enhances the selectivity of carbon monoxide production on both Ag and Au electrodes, with relatively high selectivity values of 84 % and 62 %, respectively. Additionally, the effect of varying ethylene glycol content in the choline chloride-containing electrolyte (ChCl : EG 1 : X, X=2, 3, 4) was investigated to improve the current density during CO2RR on the Ag electrode. We observed that a mole ratio of 1 : 4 exhibited the highest current density with a comparable faradaic efficiency toward CO. Notably, an evident surface reconstruction process took place on the Ag surface in the presence of Cl− ions, whereas on Au, this phenomenon was less pronounced. Overall, this study provides new insights into anion-induced surface restructuring of Ag and Au electrodes during CO2RR, and its consequences on the reduction performance on such surfaces in non-aqueous electrolytes.
AB - In this study, the effect of halide anions on the selectivity of the CO2 reduction reaction to CO was investigated in choline-based ethylene glycol solutions containing different halides (ChCl : EG, ChBr : EG, ChI : EG). The CO2RR was studied using silver (Ag) and gold (Au) electrodes in a compact H-cell. Our findings reveal that chloride effectively suppresses the hydrogen evolution reaction and enhances the selectivity of carbon monoxide production on both Ag and Au electrodes, with relatively high selectivity values of 84 % and 62 %, respectively. Additionally, the effect of varying ethylene glycol content in the choline chloride-containing electrolyte (ChCl : EG 1 : X, X=2, 3, 4) was investigated to improve the current density during CO2RR on the Ag electrode. We observed that a mole ratio of 1 : 4 exhibited the highest current density with a comparable faradaic efficiency toward CO. Notably, an evident surface reconstruction process took place on the Ag surface in the presence of Cl− ions, whereas on Au, this phenomenon was less pronounced. Overall, this study provides new insights into anion-induced surface restructuring of Ag and Au electrodes during CO2RR, and its consequences on the reduction performance on such surfaces in non-aqueous electrolytes.
KW - Electrochemical CO reduction
KW - Gold electrode
KW - Halide anion effect
KW - Non-aqueous electrolyte
KW - Silver electrode
UR - http://www.scopus.com/inward/record.url?scp=85203348498&partnerID=8YFLogxK
U2 - 10.1002/open.202400166
DO - 10.1002/open.202400166
M3 - Article
AN - SCOPUS:85203348498
SN - 2191-1363
JO - ChemistryOpen
JF - ChemistryOpen
M1 - e202400166
ER -