Thermal effects in a modified law of mass action

Non-isothermal effects in activated processes are considered by means of mesoscopic non-equilibrium thermodynamics. Charge transfer through electrode surfaces is used as a model problem. It is shown that as a generalization of classical non-equilibrium thermodynamics, the theory is capable of incorporating thermal effects into a non-linear description of activated processes. This results in a modified law of mass action accounting for non-isothermal conditions. Generalized versions of Nernst and Butler-Volmer equations allowing for thermal gradients are presented as a consequence of the modified rate law. Some distinct advantages of the formalism over its classical counterpart are discussed. (c) 2005 Elsevier B.V. All rights reserved.