Entrapment of metal nanoparticles within nanocages of mesoporous silicas aided by co-surfactants

We demonstrated an efficient approach for in situ encapsulation of metal nanoparticles (NPs) into nanocages of mesoporous silicas using a co-surfactant as the transportation medium. By using this approach, colloidal Pt and Au NPs were successfully encapsulated into the nanocages of cagelike mesoporous silicas (CMS) and FDU-12 using co-surfactants butanol and mesitylene (TMB) as the transportation medium, respectively. The prepared Pt/CMS catalysts are active and highly selective in the hydrogenation of chloronitrobenzene (CNB) to the corresponding chloroaniline (CAN). The catalyst prepared by the in situ method is superior to the catalyst prepared by the traditional solution impregnation method. This work provides a new approach for the synthesis of the mesoporous materials with encapsulated metal NPs.