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Thiol-functionalized silica colloids, grains, and membranes for irreversible adsorption of metal (oxide) nanoparticles. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 297, 46-54

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 (Impact Factor: 2.35). 04/2007; 297(1-3):46-54. 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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