CARBON INTERACTION WITH HEATED MOLYBDENUM SURFACE

High-resolution AES was used to determine the character of the process es that take place during carbon adsorption on the surface of heated ( to T almost-equal-to 1600 K) texturized Mo ribbon with a (100) face. T he products of this solid-state reaction on the surface and in the bul k of the metal were determined. Carbonization starts with surface carb ide (SC) MoC formation. After reaching the solubility limit in the sol id-state solution of carbon in molybdenum, the bulk carbide Mo2C forms under the SC and spreads to the center of the ribbon. The final stage of the carbonization is the formation of a graphite monolayer above t he bulk and surface carbides, perhaps after reaching the carbon solubi lity limit now in the bulk carbide. Carbon in the surface carbide form drastically increases the work function of the Mo(100) face from ephi = 4.45 to ephi = 5.25 eV.