Optimisation of the surface properties of SBA-15 mesoporous silica for in-situ nanoparticle synthesis

Various methods proposed for preparing nanoparticles within porous matrices involve generally the impregnation of the matrix with a solution of precursors followed by reduction based on chemical, thermal, radiolytic, or photochemical process. In most cases, the amount of solution impregnated is small and not uniformly distributed in the matrix, with a yield less than 30% and concentrated around the matrix surface. We have developed a novel method for preparing composite materials, combining impregnation under partial vacuum with radiolytic reduction. This method has enabled us to obtain SBA-15 mesoporous silicas with 50–70% impregnation and to control the nanoparticle size.