TY - JOUR
T1 - A model for low temperature electrochemical proton transfer
T2 - Temperature and isotope effects on kinetic parameters
AU - Kornyshev, A. A.
AU - Kuznetsov, A. M.
AU - Stimming, U.
PY - 1997/6/15
Y1 - 1997/6/15
N2 - Simple framework is suggested for low temperature proton transfer reactions at electrodes. Temperature and potential dependence of the electrode current and apparent transfer coefficient, αobs, are calculated. The results are in accordance with experimental observations [M. Cappadonia, S. Krause, and U. Stimming, Electrochim. Acta, 42, 841 (1997)], including the tendency for αobs extrapolated to T=0 K to approach negative values. This behavior of αobs results in a weak and rather inverse dependence of activation energy on overpotential and a strong potential dependence of the "entropic" factor. The observed isotope effect is basically accounted for by the change of the mass of the tunneling hydrogen isotope and the corresponding changes in the isotope-dependent characteristic frequencies of the medium.
AB - Simple framework is suggested for low temperature proton transfer reactions at electrodes. Temperature and potential dependence of the electrode current and apparent transfer coefficient, αobs, are calculated. The results are in accordance with experimental observations [M. Cappadonia, S. Krause, and U. Stimming, Electrochim. Acta, 42, 841 (1997)], including the tendency for αobs extrapolated to T=0 K to approach negative values. This behavior of αobs results in a weak and rather inverse dependence of activation energy on overpotential and a strong potential dependence of the "entropic" factor. The observed isotope effect is basically accounted for by the change of the mass of the tunneling hydrogen isotope and the corresponding changes in the isotope-dependent characteristic frequencies of the medium.
UR - http://www.scopus.com/inward/record.url?scp=0000614670&partnerID=8YFLogxK
U2 - 10.1063/1.473853
DO - 10.1063/1.473853
M3 - Article
AN - SCOPUS:0000614670
SN - 0021-9606
VL - 106
SP - 9523
EP - 9528
JO - Journal of Chemical Physics
JF - Journal of Chemical Physics
IS - 23
ER -