Preprint article · Journal article
Electrochemical Oxidation of CO on Cu Single Crystals under Alkaline Conditions
Department of Physics, Technical University of Denmark1
Surface Physics and Catalysis, Department of Physics, Technical University of Denmark2
Catalysis Theory Center, Department of Physics, Technical University of Denmark3
Afdelingen for Design, Maskin og Produktion, Center for Bachelor of Engineering Studies, Technical University of Denmark4
Center for Bachelor of Engineering Studies, Technical University of Denmark5
We perform a joint experimental–theoretical study of the electrochemical oxidation of CO on copper (Cu) under alkaline conditions. Using cyclic voltammetry on Cu single-crystal surfaces, we demonstrate that both Cu terraces and steps show CO oxidation activity at potentials just slightly positive (0.03–0.14 V) of the thermodynamic equilibrium potential.
The overpotentials are 0.23–0.12 V lower than that of gold (≈0.26 V), which until now has been considered to be the most active catalyst for this process. Our theoretical calculations suggest that Cu’s activity arises from the advantageous combination of simultaneous *CO and *OH adsorption under CO oxidation potentials and surmountable *CO–*OH coupling barriers.
Experimentally observed onset potentials are in agreement with the computed onsets of *OH adsorption. We furthermore show that the onsets of *OH adsorption on steps are more affected by *CO–*OH interactions than on terraces due to a stronger competitive adsorption. Overall, Cu(100) shows the lowest overpotential (0.03 V) of the facets considered.
| Language: | English |
|---|---|
| Publisher: | American Chemical Society |
| Year: | 2020 |
| Pages: | 3437-3442 |
| ISSN: | 23808195 |
| Types: | Preprint article and Journal article |
| DOI: | 10.1021/acsenergylett.0c01751 |
| ORCIDs: | Tiwari, Aarti , Bjørnlund, Anton Simon , Hochfilzer, Degenhart , Chan, Karen , Horch, Sebastian and 0000-0003-0696-8445 |
