Premium
Electrochemical cell design and experimental procedures for measuring electrode reaction kinetics at low and variable temperatures
Author(s) -
Mu Xi Hai,
Schultz Franklin A.
Publication year - 1990
Publication title -
electroanalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.574
H-Index - 128
eISSN - 1521-4109
pISSN - 1040-0397
DOI - 10.1002/elan.1140020505
Subject(s) - cyclic voltammetry , electrode , chemistry , microelectrode , standard hydrogen electrode , redox , electrochemistry , analytical chemistry (journal) , standard electrode potential , reaction rate constant , kinetics , working electrode , linear sweep voltammetry , reference electrode , electrode potential , voltammetry , inorganic chemistry , chromatography , physics , quantum mechanics
An electrochemical cell is described for measuring electrode reaction kinetics at low and variable temperatures in nonaqueous solvents. The cell contains a working electrode of conventional size (at which the standard heterogeneous electron transfer rate constant is determined by cyclic voltammetry) and a microelectrode (at which the diffusion coefficient is measured by steady‐state microelectrode voltammetry). Uncompensated solution resistance is minimized by a combination of close placement of the reference electrode salt bridge tip and the working electrode surface and instrumental positive feedback. Cell performance is evaluated by an examination of ferrocene oxidation and manganese(III) (tetraphenylporphyrin) chloride reduction at temperatures between 229 and 298 K. Comparison of the responses from these reversible and quasi‐reversible redox couples in the same solution demonstrates that the effects of uncompensated solution resistance are absent from the experimental measurements and that increases in the cyclic voltammetric peak potential separation with sweep rate are due entirely to the kinetics of the Mn(III)/Mn(II) electrode reaction.