Support effects in the break-up and aggregation of silver films under catalytic conditions

Abstract

Studies have been made of the effect of support on the sintering of silver catalysts under ethylene oxidation conditions. Measurements of the kinetics of the reorganisation of silver supported on different glassy materials have been correlated with electron spectra of the materials. The results show that sintering of silver occurs by a process of surface diffusion which is enhanced in the presence of oxygen. The nature of the support has a pronounced effect on the rate of sintering, as a result both of the surface energy of the support and of impurities, originating in the support, which diffuse to the surface of the silver.