Thiol-functionalized silica colloids, grains, and membranes for irreversible adsorption of metal(oxide) nanoparticles

Van’t Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
Colloids and Surfaces A: Physicochemical and Engineering Aspects 01/2007; DOI: 10.1016/j.colsurfa.2006.10.019
Source: OAI

ABSTRACT Thiol-functionalization is described for silica surfaces from diverging origin, including commercial silica nanoparticles and Stöber silica as well as silica structures provided by porous glasses and novel polymer-templated silica membranes. The functionalization allows in all cases for the irreversible binding of metal(oxide) particles from a solution. Examples are the adsorption of CoFe2 O4 particles for the preparation of magnetizable silica colloids and silica structures, and gold nanoparticles that directly nucleate and grow on thiol-functionalized silica in a solution of HAuCl4 upon addition of a reducing agent.

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