Oxygen-induced buildup of W(100) and W(111) planes

Abstract

Adsorption and desorption of oxygen on the W (100) and the W (111) planes have been studied by using a probe-hole field emission microscope. When an emitter covered with adsorbed oxygen is gradually heated from 291K to 1800K, the minimum increments of work functions on the W(100) and W(111) planes are respectively ΔØ 100 min = -0.30 eV at 1750 K and ΔØ 111 min = -0.50 eV at 1700K. The experimental results on the W (100) and the W (111) planes are compared. And the physical explanation of the minimum work-function increments is given.