Reaction Mechanism of V(Ⅳ)/V(Ⅴ) Redox Couple at Graphite Felt Composite Electrode Bonded with Conductive Carbon Plastic

Authors

Xiao-gang LI, School ofChemistry and Chemical Engineering,Central South University,Changsha410083,Hunan,China;
Ke-long HUANG, School ofChemistry and Chemical Engineering,Central South University,Changsha410083,Hunan,China;
LIUSu-qin LIUSu-qin, School ofChemistry and Chemical Engineering,Central South University,Changsha410083,Hunan,China;
Ning TAN, School ofChemistry and Chemical Engineering,Central South University,Changsha410083,Hunan,China;
Li-quan CHEN, School ofChemistry and Chemical Engineering,Central South University,Changsha410083,Hunan,China;Institute ofPhysics,Chinese Academy ofSciences,Beijing100080,China;

Corresponding Author

Ke-long HUANG

Abstract

The rate-determining step of V(Ⅳ) /V(Ⅴ) redoxreaction was investigated at graphite felt(GF)composite electrode by various techniques: cyclic voltammetry,polarization curve and impedance spectroscopy.Cyclic voltammetry analysis indicated that V(Ⅳ) /V(Ⅴ) redox reaction at GF electrode is quasi reversible.Acertain chemical reaction step is suspected to follow the electron transfer step of this reaction.The Tafel slopevalue(0.124) obtained from the polarization curve agrees well with theoretical value(0.12),which supposingthe electron transfer step was the rate-determining step.Impedance Spectroscopies at various potentials werestudied and simulated by equivalentcircuits.The impedance value of the electron transfer step modified is greatlyhigher than the others,which shows that the electron transfer step is the rate-determining step.This further con-firms the conclusion obtained by polarization curve test.

Keywords

graphite felt, rate-determining step, vanadium redox battery, V(Ⅳ) / V(Ⅴ)

DOI Link

https://doi.org/10.61558/2993-074X.1754

Publication Date

2006-11-28

Online Available Date

2006-11-28

Revised Date

2006-11-28

Received Date

2006-11-28

Recommended Citation

Xiao-gang LI, Ke-long HUANG, LIUSu-qin LIUSu-qin, Ning TAN, Li-quan CHEN. Reaction Mechanism of V(Ⅳ)/V(Ⅴ) Redox Couple at Graphite Felt Composite Electrode Bonded with Conductive Carbon Plastic[J]. Journal of Electrochemistry, 2006 , 12(4): 368-372.
DOI: 10.61558/2993-074X.1754
Available at: https://jelectrochem.xmu.edu.cn/journal/vol12/iss4/3