Molecular dynamics simulation on the interaction of CeO2 and silane coupling agent in solutions

The adsorption of silane coupling agent at different CeO2 surfaces in different solutions are studied by molecular dynamics simulation. Both single adsorbed silane molecule and multiple adsorbed silanes are modeled and the adsorption energy, radial distribution functions, orientation and alignment of these adsorbates are analyzed. Silane molecules exhibit stronger interaction with CeO2 (1 1 1) surface than with surface (1 1 0) and (1 0 0). The polarity of solvent affects the orientation and alignment of silanes at solid surface. In addition, the interaction between silane and the solid surface decreased with the increase of the polarity of the solvents. Meanwhile, the number of adsorbed silane molecules within a silane layer depends on the polarity of the solvents, which is 1.28 silanes/nm2 and 2.14 silanes/nm2 in water and in organic solvents, respectively.