Abstract
The electrochemical reduction at platinum electrodes of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in the presence of Na+ in acetonitrile solution was studied using various electrochemical measurements under conditions with significant mass transport, namely channel flow- and sono-voltammetries. In channel electrode voltammetry, the presence of Na+ was observed to change the voltammetric response from that of pure DDQ alone. In particular, at potentials corresponding, in the absence of Na+, to the two electron reduction step of DDQ, a spike-like increase and decrease of reductive current was observed on negative going potential scans after which the current returned to the level expected for a one-electron reduction. This behavior can be explained by the following reaction scheme with the formation of a passivated surface due to the adsorption of Na2+ DDQ2-. DDQ2-+Na+→Na+DDQ2- Na+DDQ2-→Na+DDQads2- Na+DDQads2-+Na+DDQ ads2-→Na2+ DDQads2-+DDQ2- This scheme was found to be consistent with independent sono-voltammetric data and with in situ electrochemical ESR measurements.
Original language | English |
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Pages (from-to) | 193-201 |
Number of pages | 9 |
Journal | Journal of Electroanalytical Chemistry |
Volume | 451 |
Issue number | 1-2 |
DOIs | |
Publication status | Published - Jul 1 1998 |
Externally published | Yes |
ASJC Scopus Subject Areas
- Analytical Chemistry
- General Chemical Engineering
- Electrochemistry
Keywords
- 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone
- Acetonitrile solution
- Electrochemical reduction
- Na
- Platinum electrodes