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Fluctuation enhanced electrochemical reaction rates at the nanoscale.

ABSTRACT: The electrode potential constitutes a dynamical variable whenever an electrode is resistively coupled to the electric circuit. We show that at the nanoscale, the discreteness and stochasticity of an electron transfer event causes fluctuations of the electrode potential that render all elementary electrochemical reactions to be faster on a nanoelectrode than predicted by the macroscopic (Butler-Volmer) electrochemical kinetics. This phenomenon is substantiated by means of a generalized (electro)chemical master equation.

SUBMITTER: Garcia-Morales V

PROVIDER: S-EPMC2842024 | biostudies-other | 2010 Mar

REPOSITORIES: biostudies-other

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Fluctuation enhanced electrochemical reaction rates at the nanoscale.

García-Morales Vladimir V Krischer Katharina K

Proceedings of the National Academy of Sciences of the United States of America 20100222 10

The electrode potential constitutes a dynamical variable whenever an electrode is resistively coupled to the electric circuit. We show that at the nanoscale, the discreteness and stochasticity of an electron transfer event causes fluctuations of the electrode potential that render all elementary electrochemical reactions to be faster on a nanoelectrode than predicted by the macroscopic (Butler-Volmer) electrochemical kinetics. This phenomenon is substantiated by means of a generalized (electro)c ...[more]

PMID: 20176966

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