On the catalytic activity of silver: I. Activity, poisoning, and regeneration during the decomposition of hydrogen peroxide

Abstract

The catalytic decomposition of hydrogen peroxide on silver has been studied with special reference to activity changes of the catalyst.Initial-rate measurements confirm our previous results from concentration-change measurements. The reaction is of second order in 10–25 M solutions; in the range of lower concentrations it follows first order kinetics.During the decomposition the catalytic activity of silver is reduced, depending on the solution concentration and various other experimental conditions. The poisoning is caused by a partly irreversible sorption of the reaction product oxygen; oxide layers are formed only in 2–5 M H2O2 solutions. The course of the poisoning was studied in some detail.Decomposition and poisoning are scarcely at all influenced by the effects of metal dissolution by the reactants, by the surface changes or by the silver ions evolved.