Functionalized Monolayers on Ordered Mesoporous Supports

TLDR

The study presents a surface modification scheme that enables rational design of tailored porous materials for environmental and industrial applications. The authors synthesized mesoporous silica materials functionalized with organic monolayers. The resulting cross‑linked mercaptopropylsilane monolayers, up to 76 % surface coverage, enable highly efficient, stable, and regenerable removal of mercury and other heavy metals from aqueous and nonaqueous waste streams, achieving distribution coefficients up to 340,000.

Abstract

Mesoporous silica materials containing functionalized organic monolayers have been synthesized. Solid-state nuclear magnetic resonance suggests that a cross-linked monolayer of mercaptopropylsilane was covalently bound to mesoporous silica and closely packed on the surface. The relative surface coverage of the monolayers can be systematically varied up to 76 percent. These materials are extremely efficient in removing mercury and other heavy metals from both aqueous and nonaqueous waste streams, with distribution coefficients up to 340,000. The stability of these materials and the potential to regenerate and reuse them have also been demonstrated. The surface modification scheme reported here enables rational design of the surface properties of tailored porous materials and may lead to the synthesis of more sophisticated functionalized composites for environmental and industrial applications.