Encapsulated Nanoparticles

摘要

The invention relates to a composite substance comprising particles of an oxide of a metal dispersed in a porous silica matrix. The composite substance may be made by preparing a solution comprising a soluble salt of the metal and a surfactant; adjusting the solution to a basic pH at which a hydroxide of the metal precipitates from the solution; preparing an aqueous suspension of the hydroxide of the metal, said suspension being at pH greater than 7; adding to the suspension, with agitation, an alkoxysilane, so as to form composites comprising the hydroxide of the metal at least partially coated with silica; and calcining these composites so as to produce the composite substance.