Abstract
The interaction of hydrogen sulphide with lead films which have chemisorbed oxygen has been investigated in the temperature range 80 to 290 K by X-ray induced photoelectron spectroscopy. Removal of oxygen is complete at 290 K with its replacement by a surface sulphide. At lower temperatures intermediate steps in the surface reduction process have been isolated. An unambiguous interpretation of previously published work function and adsorption data is now possible.