Facial reconstruction

Search LJMU Research Online

Browse Repository | Browse E-Theses

In situ electrochemical electron paramagnetic resonance spectroscopy as a tool to probe electrical double layer capacitance.

Wang, B, Fielding, AJ and Dryfe, RAW (2018) In situ electrochemical electron paramagnetic resonance spectroscopy as a tool to probe electrical double layer capacitance. Chemical communications (Cambridge, England), 54 (31). pp. 3827-3830. ISSN 1364-548X

[img] Text
In situ electrochemical electron paramagnetic resonance spectroscopy as a tool to probe electrical double layer capacitance..pdf - Accepted Version
Restricted to Repository staff only until 15 March 2019.

Download (666kB)

Abstract

Electron paramagnetic resonance (EPR) spectroscopy is applied in situ to monitor the electrochemical capacitance of activated carbon in aqueous solutions, thereby revealing aspects of the charge storage mechanism. The EPR signal of activated carbon increases during the charging process and returns reversibly when discharged. Simulation of the spectral lineshape and its temperature dependence indicate that two kinds of spins exist: spin at defects giving rise to a narrow signal, and spins associated with surface-bound aromatic moieties causing a broad signal. A potential-dependent response of the narrow feature is seen in each of the electrolyte solutions used, while changes of the broad feature occur only at higher electrolyte concentrations. The results suggest that the observed increase of unpaired electron density on activated carbon is due to the formation of radical species due to reduction of functional groups. The potential dependence of the broad feature at higher electrolyte concentrations may be related to the further adsorption of ions into the deep porous structure of activated carbon.

Item Type: Article
Uncontrolled Keywords: 03 Chemical Sciences
Subjects: Q Science > QD Chemistry
Divisions: Pharmacy & Biomolecular Sciences
Publisher: The Royal Society of Chemistry
Related URLs:
Date Deposited: 03 May 2018 09:12
Last Modified: 22 Sep 2018 15:45
DOI or Identification number: 10.1039/C8CC00450A
URI: http://researchonline.ljmu.ac.uk/id/eprint/8613

Actions (login required)

View Item View Item