| Abstract
| - Fluorinated alcohols and fluorinated ethers adsorbed on carbon films have been studied in order tomodel the surface chemistry of Fomblin Zdol lubricants on the carbon-coated surfaces of magnetic datastorage media. The model compounds used were 2,2,2-trifluoroethanol (CF3CH2OH), which is representativeof the end groups of Fomblin Zdol, and perfluorodiethylether (CF3CF2)2O, which represents the main chainof Fomblin Zdol. Temperature-programmed desorption (TPD) spectroscopy was used to measure thedesorption energies of these compounds on a variety of different carbon films. Desorption energies weremeasured on amorphous hydrogenated carbon (a-CHx), amorphous nitrogenated carbon (a-CNx), cathodicarc carbon (CAC), and ion-beam sputtered carbon (IBC). On all carbon film surfaces the desorption energyof CF3CH2OH is higher than that of (CF3CF2)2O. The desorption energy of CF3CH2OH is higher on thea-CNx films than on the other carbon films; however, the desorption energy of (CF3CF2)2O does not dependon the type of carbon. Finally, the desorption energies are dependent upon CF3CH2OH and (CF3CF2)2Ocoverage, indicating that the carbon films are heterogeneous and expose binding sites with a range ofaffinities for adsorption. Systematic measurements of the desorption energies over a range of coverageshave been used to map out the heterogeneity of all the carbon films.
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