Soft route for monodisperse gold nanoparticles confined within SH-functionalized walls of mesoporous silica

In this paper, we report a soft route leading to small gold nanoparticles confined within the framework of 2D-hexagonal mesoporous SH-functionalised silicas. For that purpose, a hydrophilic bis-silylated precursor containing a disulfide unit was prepared. Framework-functionalised materials were obtained in one step by the "direct synthesis'' method which consists of a co-hydrolysis and polycondensation of a bridged organosilica precursor with tetraethylorthosilicate (TEOS) in the presence of a non-ionic triblock co-polymer (P123) as structure-directing agent. Reduction of SS groups leads quantitatively to SH functional groups within the framework of 2D hexagonal mesoporous silicas. All these materials have been characterised by TEM, (13)C and (29)Si NMR experiments, nitrogen gas adsorption, powder XRD and elemental analysis. The subsequent growth of monodisperse gold nanoparticles of small size (similar to 2 nm) within the walls of mesoporous materials was studied and is discussed.