Probing TCNQ-Mediated Metal Reduction Reactions at Liquid-Liquid Interface with SECM

No Thumbnail Available
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Date
2020-05-01
Major/Subject
Mcode
Degree programme
Language
en
Pages
Series
ELECTROANALYSIS
Abstract
Metal reduction at the interface between two immiscible electrolyte solutions (ITIES) has been studied with scanning electrochemical microscopy (SECM). Metal cations in the aqueous phase are reduced by 7,7,8,8-tetracyanoquinodimethane anion (TCNQ −) residing in the oil phase, methyl isobutyl ketone (MIBK). TCNQ − is formed at the SECM tip by reducing TCNQ, which results in a positive feedback loop between the tip and the ITIES when an electron is donated to a metal cation. The effect of the Galvani potential difference on the rate of the interfacial electron transfer was investigated, establishing the potential difference either by an additional substrate electrode in the aqueous phase or by an a common ion in both phases. It is shown that the Galvani potential difference as a driving force does enable TCNQ − mediated Cu 2+ reduction. Finite element method (FEM) simulations were run to provide information on the reaction kinetics and stoichiometry.
Description
Keywords
Scanning electrochemical microscope, liquid-liquid interface, metal reduction, Finite element method (FEM), Electrochemistry
Citation
Nieminen , E , Kazimova , N & Murtomäki , L 2020 , ' Probing TCNQ-Mediated Metal Reduction Reactions at Liquid-Liquid Interface with SECM ' , Electroanalysis , vol. 32 , no. 5 , pp. 949-957 . https://doi.org/10.1002/elan.201900571