Lateral adsorbate interactions inhibit HCOO⁻ while promoting CO selectivity for CO₂ electrocatalysis on silver

Lateral adsorbate interactions inhibit HCOO⁻ while promoting CO selectivity for CO₂ electrocatalysis on silver

Bohra, D. (TU Delft ChemE/Materials for Energy Conversion and Storage)
Ledezma Yanez, I.D. (TU Delft Large Scale Energy Storage)
Li, G. (TU Delft ChemE/Catalysis Engineering)
de Jong, W. (TU Delft Large Scale Energy Storage)
Pidko, E.A. (TU Delft ChemE/Inorganic Systems Engineering)
Smith, W.A. (TU Delft ChemE/Materials for Energy Conversion and Storage)

2019

Ag is a promising catalyst for the production of carbon monoxide (CO) via the electrochemical reduction of carbon dioxide (CO₂ER). Herein, we study the role of the formate (HCOO⁻) intermediate *OCHO, aiming to resolve the discrepancy between the theoretical understanding and experimental performance of Ag. We show that the first coupled proton-electron transfer (CPET) step in the CO pathway competes with the Volmer step for formation of *H, whereas this Volmer step is a prerequisite for the formation of *OCHO. We show that *OCHO should form readily on the Ag surface owing to solvation and favorable binding strength. In situ surface-enhanced Raman spectroscopy (SERS) experiments give preliminary evidence of the presence of O-bound bidentate species on polycrystalline Ag during CO₂ER which we attribute to *OCHO. Lateral adsorbate interactions in the presence of *OCHO have a significant influence on the surface coverage of *H, resulting in the inhibition of HCOO⁻ and H₂ production and a higher selectivity towards CO.

adsorbate-adsorbate interactions
DFT
electrocatalysis
in situ studies
Raman spectroscopy

http://resolver.tudelft.nl/uuid:e9ff48d3-c779-4257-b881-85d09bd41929

https://doi.org/10.1002/anie.201811667

1433-7851

Angewandte Chemie (International Edition), 58 (5), 1345-1349

Institutional Repository

journal article

© 2019 D. Bohra, I.D. Ledezma Yanez, G. Li, W. de Jong, E.A. Pidko, W.A. Smith