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

Gold nanoparticles in the cores coated by non-porous silica shells ([email protected]2) and by porous silica shells ([email protected]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. [email protected]2 nanoparticles well catalyze the reduction and oxidation reactions while [email protected]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.