Successive use of amphiphilic block copolymers as nanoreactors and templates: Preparation of porous silica with metal nanoparticles

A new way for preparation of microporous silica containing metal nanopartic les inside pores is described. Special amphiphilic block copolymers, polybu tadiene-b-poly( ethylene oxides), are used in a first step as nanoreactors for the preparation of metal nanoparticles inside their micelle cores and t hen as templates where the micelles act as porogens. The final product afte r calcination of the polymer is silica where catalytically interesting nano particles with controlled size, shape, and distribution are located on the pore walls. Control for nanoparticle growth and location is provided by the reduction conditions.