Chlorination reaction and laser stimulated desorption from Ag surfaces

Abstract

Formation of AgCl on Ag surfaces exposed to Cl2 and laser stimulated desorption from chlorinated Ag surfaces have been studied. For Cl2 exposures less than 107 L, a logarithmic time dependence of the AgCl2 reaction is observed. Due to effective subsurface diffusion, the surface layer is Ag enriched with respect to stoichiometric AgCl. At higher exposures, a t 1 2 time dependence indicates that the diffusion process becomes reaction rate limiting and a stoichiometric AgCl surface layer is formed. UV/visible laser stimulated desorption of neutral Cl, Ag and AgCl species is observed for laser power less than 150 MW cm-2. The desorption process is found to be non-thermal in nature. A desorption mechanism based on electronic excitations is discussed. © 1985.