Multilayer Adsorption of Methane and Chloromethane on the Molybdenum (100) Surface

Abstract

Using all-atom molecular dynamics simulations, the multilayer adsorption of two single-carbon alkane analogues methane (CH 4 ) and chloromethane (CH 3 Cl)in the liquid phase on a metallic substrate (molybdenum (100) surface) has been studied to elucidate differences in the adsorbed film structure as a function of the overall film thickness, system temperature, substrate mobility, and pairwise substrate interaction potential (Lennard-Jones 12-6 versus embedded atom method versus Lennard-Jones 9-3 "wall" potential, used as a basis for comparison). Simulations suggest a clear predilection to well-ordered packing arrangements dictated by the adsorbate molecular geometry when adsorbed on the flat, featureless Lennard-Jones wall, but adsorption on the atomistic molybdenum substrate exhibits a more complex structure and orientation influenced by the adsorbate molecular geometry but also dependent on the presence or lack of small variations in surface structure caused by substrate mobility and interatomic potential. The result illustrates differences in packing geometry and surface binding energy on very noticeable scales despite the magnitude of surface vibrations allowed.

Adsorption of small hydrocarbons on rutile TiO2(110)

“…The interaction of hydrocarbons with single crystal metal surfaces has been extensively studied over the past decades [2,. The results of these studies indicate that alkanes can physisorb, chemisorb, or react with adsorbates already on the surface, depending on metal substrate, surface temperature and other experimental conditions [11][12][13][14][15][16][17][18][19]. While the exact adsorption energies depend on the metal and its surface structure, a linear dependence of the adsorption energy on molecular chain length is generally observed for the adsorption of short alkanes on many metal surfaces [2,[20][21][22][23]39].…”

Adsorption of Methyl Chloride on Molecular Sieves, Silica Gels, and Activated Carbon

“…There have been a number of isolated studies on the adsorption of MeCl on various adsorbents, such as metal surfaces , , , charcoal , , silica gels , , zeolites , and activated carbon fibers ; see Tab. for a summary of few selected studies.…”