TEMPERATURE-DEPENDENT ADSORPTION OF ARGON ON GOLD: A MOLECULAR DYNAMICS STUDY
SR Easter and CH Baker and PM Norris, PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION, 2014, VOL 8B, UNSP V08BT10A067 (2015).
When a gas and solid surface are brought into contact, some gas atoms may adsorb onto the surface, forming one or more denser layers. Adsorption has direct uses in many technologies, for instance filtration and pharmacology, and the prevalence of gas-solid interfaces means that it impacts many other technologies. However much is still unknown concerning the microscopic dynamics of adsorption. To investigate the effect of temperature on adsorption, molecular dynamics simulations were performed on an interface between solid gold and gaseous argon. The gas was placed in contact with the solid, allowing adsorption of gas atoms under a constant system temperature. The results of the simulations were analyzed to study the effect of temperature on the density of the adsorbed layer and its rate of formation. When brought into contact, the gas adsorbed to form one or more layers, the density of which was found to be strongly temperature-dependent. A monolayer was observed for temperatures above 150 K while below that value a secondary layer formed. Simulations above 450 K showed an exponential relationship between mean steady-state density and temperature of the form D-eq = alpha e(beta T).
Return to Publications page