(757j) A Theoretical Study of Bulk and Inhomogeneous Hydration of Primary Amines

A Theoretical Study of Bulk and Inhomogeneous Hydration of Primary
Amines

Shijie Sheng, Jia Fu and Jianzhong Wu*

Department of
Chemical and Environmental Engineering,

University of
California, Riverside, CA 92521

Abstract

Amine functionalized surfaces are
relevant to various industrial applications, for example, dye decomposition, carbon
dioxide fixation and heavy metal enrichment from waste water. The surface
effect on amine hydration plays a pivotal role in particular for applications
with surface reactions. This work aims to unravel the change in the hydration
structure of primary amines due to the presence of a silica surface at
different solution conditions. To calibrate our theoretical predictions based
on the molecular density functional theory, all-atom molecular dynamic (MD)
simulations are first applied to a silica slab with amine molecules tethered
onto a silica surface at representative pH values. In comparison to amine
solvation in the bulk phase, both theoretical and simulation results indicate
that the silica surface alters the hydration structure sensitive to the pH and the
chain length of the primary amine. The effects of silica surface on the hydration-bonding
dynamics are also studied.