Study of adsorption on metals by the contact potential technique

Abstract

The change in contact potential between metals due to physical adsorption of water vapour, isopropanol, and ethyl acetate has been studied. The plot of contact potential against relative vapour pressure showed a hysteresis loop, the behaviour varying for different methods of surface preparation. An initial irreversible potential change was always found, due to chemisorption. By studying the dependence of the contact potential on the temperature of one of the metal surfaces it has been possible to determine the change in work function of a gold surface due to physical adsorption.