Gold@silica catalyst: porosity of silica shells switches catalytic reactions

Abstract Gold nanoparticles in the cores coated by non-porous silica shells (Au@nSiO 2 ) and by porous silica shells (Au@pSiO 2 ) were synthesized and used to catalyze the reduction and oxidation reactions to understand the influence of the structure of silica shells on their catalytic activity. Au@pSiO 2 nanoparticles well catalyze the reduction and oxidation reactions while Au@pSiO 2 nanoparticles are inactive for those reactions. The characterizations combining with catalytic reactions reveal that the porosity of silica shells is responsible for catalytic activity.