Facile fabrication and application of Au@MSN nanocomposites with a supramolecular star-copolymer template

Mesoporous silica nanoparticles (MSNs) with soft templates were readily fabricated using a sol-gel process under mild conditions. The soft templates were composed of an amphiphilic supramolecular star-copolymer from anionic monocarboxyl polydimethylsiloxane and cationic hyperbranched polyethyleneimine via the electrostatic interaction. Ascribed to the high accessibility of dendritic architecture for small molecules and the existence of plentiful amino groups, these supramolecular dendritic templates in MSNs could be used directly as the nanoreactors and reducing reagents for the in situ reduction of chloroauric acid (HAuCl(4)). The resultant Au@MSN nanocomposites showed excellent catalytic performance in a reduction reaction of 4-nitrophenol by sodium borohydride (NaBH(4)).