The role of the copper oxidation state in the electrocatalytic reduction of CO2 into valuable hydrocarbons

Velasco-Vélez, J-J, Jones, TE, Gao, D, Carbonio, E, Arrigo, R ORCID: https://orcid.org/0000-0002-2877-8733, Hsu, C-J, Huang, Y-C, Dong, CL, Chen, J-M, Lee, J-F, Strasser, P, Roldan-Cuenya, B, Schloegl, R, Knop-Gericke, A and Chuang, C 2018, 'The role of the copper oxidation state in the electrocatalytic reduction of CO2 into valuable hydrocarbons' , ACS Sustainable Chemistry & Engineering, 7 (1) , pp. 1485-1492.

[img]
Preview
PDF (Accepted manuscript) - Accepted Version
Download (889kB) | Preview
[img]
Preview
PDF (Supplementary data) - Accepted Version
Download (664kB) | Preview

Abstract

Redox-active copper catalysts with accurately prepared oxidation states (Cu0, Cu+ and Cu2+) and high selectivity to C2 hydrocarbon formation, from electrocatalytic cathodic reduction of CO2, were fabricated and characterized. The electrochemically prepared copper-redox electro-cathodes yield higher activity for the production of hydrocarbons at lower oxidation state. By combining advanced X-ray spectroscopy and in situ micro-reactors it was possible to unambiguously reveal the variation in the complex electronic structure that the catalysts undergo at different stages (i.e. during fabrication and electrocatalytic reactions). It was found that the surface, sub-surface and bulk properties of the electrochemically prepared catalysts are dominated by the formation of copper carbonates on the surface of cupric-like oxides, which prompts catalyst deactivation by restraining effective charge transport. Furthermore, the formation of reduced or partially-reduced copper catalysts yields the key dissociative proton-consuming reactive adsorption of CO2 to produce CO, allowing the subsequent hydrogenation into C2 and C1 products by dimerization and protonation. These results yield valuable information on the variations in the electronic structure that redox-active copper catalysts undergo in the course of the electrochemical reaction, which, under extreme conditions are mediated by thermodynamics but, critically, kinetics dominate near the oxide/metal phase transitions.

Item Type: Article
Schools: Schools > School of Environment and Life Sciences > Biomedical Research Centre
Journal or Publication Title: ACS Sustainable Chemistry & Engineering
Publisher: ACS Publications
ISSN: 2168-0485
Depositing User: Dr R Arrigo
Date Deposited: 04 Dec 2018 11:54
Last Modified: 29 Nov 2019 02:30
URI: http://usir.salford.ac.uk/id/eprint/49107

Actions (login required)

Edit record (repository staff only) Edit record (repository staff only)