Design of highly stable, ordered cage mesostructured monoliths with controllable pore geometries and sizes

A simple strategy in terms of fabrication time (within minutes) and composition phase domains was used to design optical cage mesostructured silica monoliths with shape- and size-controlled cavities and entrance pores, large-sized glass (crack-free), thick-walled framework up to 20 nm thick, uniformly sized mesopores of ∼14 nm, and cubically ordered geometries. This is the first report of using a rapid templating method in microemulsion systems to fabricate mesoscopically ordered silica/copolymers composites that have cage structures. With use of this strategy, which is based on an instant direct-templating method, the size of the cavities and entrance pores of highly ordered monolithic cages (designated as HOM-C) were enlarged by a high concentration of copolymers (EO_mPO_nEO_m) used in the composition phase domains, by a high degree of swelling, and by large PO-EO blocks (core-corona) of the copolymer templates. Our strategy enables actual control over the phase structures of the copolymers. Thus, a family of cubic cage mesostructured monoliths was feasibly fabricated in large orientationally ordered domains. The HOM-C structures fabricated here exhibited long-term retention (about a month) of the hierarchically ordered structures under extreme hydrothermal conditions. Our results show evidence that the size and shape of the connecting pores and the nature of the spherical cavity of the cage geometry crucially influenced the retention of the HOM-C cage character when the monolith was subjected to hydrothermal treatment such as boiling water.