Preparation of bicontinuous mesoporous silica and organosilica materials containing gold nanoparticles by co-synthesis method

Abstract

Catalytic activities of gold strongly depend on its particle size. It is necessary to have homogeneous distributions of small gold nanoparticles with diameters between 2 and 5 nm for excellent catalytic activities. In this study, gold-containing mesoporous silica materials were prepared by a co-synthesis method. The essence of this sol–gel co-synthesis method is to combine together neutral surfactant template synthesis of mesoporous silica materials with the introduction of metal ions via bifunctional silane ligands, so that the formation of mesostructures and metal–ion doping occur simultaneously. The formation of gold nanoparticles with size less than 5 nm inside mesoporous materials (HMS, MSU, and PMO) has been achieved by this co-synthesis sol–gel process. In addition, the effects of post-treatments, such as calcination and reduction, on pore structures and nanoparticle size distributions were also investigated.