High capacity surface route discharge at the potassium-O2 electrode

Chen, Yuhui, Jovanov, Zarko P., Gao, Xiangwen, Liu, Jingyuan, Holc, Conrad, Johnson, Lee R. and Bruce, Peter G. (2018) High capacity surface route discharge at the potassium-O2 electrode. Journal of Electroanalytical Chemistry, 819 . pp. 542-546. ISSN 1873-2569

[img]
Preview
PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Available under Licence Creative Commons Attribution.
Download (913kB) | Preview

Abstract

Discharge by a surface route at the cathode of an aprotic metal-O2 battery typically results in surface passivation by the non-conducting oxide product. This leads to low capacity and early cell death. Here we investigate the cathode discharge reaction in the potassium-O2 battery and demonstrate that discharge by a surface route is not limited to growth of thin (<10 nm) metal oxide layers. Electrochemical analysis and in situ Raman confirmed that the product of the cathode reaction is a combination of KO2 and K2O2, depending on the applied potential. Use of the low donor number solvent, acetonitrile, allows us to directly probe the surface route. Rotating ring-disk electrode, electrochemical quartz crystal microbalance and scanning electron microscope characterisations clearly demonstrate the formation of a thick > 1 μm product layer, far in excess of that possible in the related lithium-O2 battery. These results demonstrate a high-capacity surface route in a metal-O2 battery for the first time and the insights revealed here have significant implications for the design of the K-O2 battery.

Item Type: Article
Keywords: Metal-air; Oxygen reduction
Schools/Departments: University of Nottingham, UK > Faculty of Science > School of Chemistry
Identification Number: https://doi.org/10.1016/j.jelechem.2018.03.041
Depositing User: Smith, Ruth
Date Deposited: 27 Mar 2018 10:35
Last Modified: 08 May 2020 11:45
URI: https://eprints.nottingham.ac.uk/id/eprint/50717

Actions (Archive Staff Only)

Edit View Edit View