Standard Article

Kinetics of electrochemical reactions

Fundamentals and Survey of Systems

Thermodynamics and kinetics of fuel cell reactions

  1. A. Hamnett

Published Online: 15 DEC 2010

DOI: 10.1002/9780470974001.f101005

Handbook of Fuel Cells

Handbook of Fuel Cells

How to Cite

Hamnett, A. 2010. Kinetics of electrochemical reactions. Handbook of Fuel Cells. .

Author Information

  1. University of Strathclyde, Glasgow, UK

Publication History

  1. Published Online: 15 DEC 2010

Abstract

This chapter explores the dependence of the rate of electrochemical reactions on the potential difference accommodated in the double layer. The concept of overpotential is introduced, and the theory of electron transfer at the electrode–electrolyte interface described. The derivation of the Butler–Volmer equation is shown to depend on the reorganization energy of the fundamental electrochemical reaction being large compared to the electrical energy associated with the electron transfer process across the interface. The pre-exponential expression in the Butler–Volmer equation, the exchange current, is shown to depend on the fundamental kinetics of the electrochemical reaction, and some simple examples are given.

Keywords:

  • overpotential;
  • reorganization energy;
  • Butler–Volmer equation;
  • exchange-current density;
  • Franck–Condon principle