Surface study of the bonding nature of ambient adsorbates to nickel alloy substrates using thermal desorption and X-ray photoelectron spectroscopy

The present study analyzed the surface effects resulting from cleaning of a Ni alloy with different solvents using an approach involving thermal desorption and X-ray photoelectron spectroscopy. The study focused on contaminant O and C species interactions with the polycrystalline substrate resulting from various solventrambient interactions. Each solvent resulted in evaporation and ambient adsorption behavior which produced contaminants characteristic of the solvent used. Combining desorption theory and surface spectroscopic techniques, a method of determining desorption behavior, independent of weight measurements, was developed. By comparison of ambient O species to substrate oxides, changes in adsorbate coverage were estimated for the denuding surfaces. Experimental values for desorption behaviors and relative desorption energetics were determined for ambient air on a polycrystalline substrate resulting from solventrsubstrate interactions. Differences were discriminated between the preparation methods and shown to vary as a function of solvent used. The nature of a surface with contamination was explained on this basis. q1999 Elsevier Science B.V. All rights reserved.