J. Phys. II France
Volume 4, Numéro 9, September 1994
Page(s) 1605 - 1616
DOI: 10.1051/jp2:1994220
J. Phys. II France 4 (1994) 1605-1616

The initiating rate of a heterogeneous reaction

Yu. A. Buyevich1, 2 and M. V. Tret'yakov2

1  Laboratoire d'Aerothermique du CNRS, 92190 Meudon, France
2  Department of Mathematical Physics, Urals State University, 620 083 Ekaterinburg, Russia

(Received 15 July 1993, revised 24 April 1994, accepted 19 May 1994)

A stochastic model of nucleation and subsequent growth of new phase islands on solid surfaces is proposed and expressions for the mean induction time and its variance are obtained in an explicit form. The intermediate stage of the new surface phase evolution is studied under conditions of the supersaturation gradually decreasing as a result of the growth of the islands. The island size distribution as well as the supersaturation and the fraction of the surface area covered with the new phase are found as functions of time. It is proved that both the induction period and decrease in surface metastability must be taken into account when trying to treat the surface reaction kinetics, and some conclusions of conventional models with no allowance for the aforementioned factors have certainly to be revised.

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