Untersuchung der Gasadsorption im Feldelektronenmikroskop in Abhängigkeit von Strom und Spannung

Abstract

In studies of gas adsorption on metals with the aid of the field emission microscope influences of the electric field or the current on the adsorption have been reported. In the present paper we succeed in seperating the effects of field and current by using pulsed field emission with a variable voltage in the interval between pulses. We find that the electric field is of no influence, that larger currents, however, result in an increase in the speed of adsorption. Possible mechanisms are discussed. A new method for measuring the change in work function on adsorption is reported. With this method the change in work function during the adsorption of O₂ on tungsten has been measured.