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A series of hierarchically ordered porous silica composites were synthesized using anionic (SO4 -2) polystyrene spheres and triblock copolymers Pluronic F127 (EO107PO70EO107) and P123 (EO20PO70EO20) as templates in the presence of cosurfactants (n-alcohols) in an acidic medium. The silica materials were characterized by XRD, SEM, TEM, Hg porosimetry, N2 adsorption, solid-state NMR, and TG-DTA. At least three distinct pore sizes are observed in these materials. The composites consist of three-dimensional ordered macrospheres (200−800 nm) with interconnecting uniform-sized (70−130 nm) windows. The walls of these macrospheres consist of mesostructured pores (3−8 nm). Nitrogen adsorption indicates the presence of microporosity (<2 nm). Here, we report the detailed synthesis and characterization of such hierarchically ordered porous silica composites (Sen et al. U.K. Patent, GB 0201951.1; Angew. Chem., Int. Ed. 2003, 42, 4649) with macro−meso−microporous structure and a three-dimensional interconnectivity. These materials could be useful as potential supports for heterogeneous catalysis for bulkier molecules where diffusion of reactant molecules could be facilitated.

An entirely synthetic method is used to produce hierarchically ordered porous silica materials in a one‐pot synthesis, with ordering on three different scales; that is, macropores (200–800 nm), interconnecting windows (70–130 nm), ordered mesoporous walls (80 nm) with narrow micropores (<2 nm) in the presence of multiple templates (see picture). At the macro‐ and mesoscale both ordering and size is controlled whilst at the microscale the interconnectivity is controlled.

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The successfuls ynthesis of hierarchically structured titaniums ilicalite-1 (TS-1) with large intracrystalline macroporesb ys team-assisted crystallisation of mesoporous silica particlesi sr eported. The macropore topologyw as imaged in 3D by using electron tomographya nd synchrotron radiation-based ptychographic X-ray computed tomography,r evealing interconnected macropores within the crystals accounting for about3 0% of the particle volume. The study of the macropore formation mechanism revealed that the mesoporous silica particles act as as acrificial macropore template during the synthesis. Silicon-to-titanium ratio of the macroporous TS-1 samples was successfully tuned from 100 to 44. The hierarchically structured TS-1 exhibited high activity in the liquid phase epoxidation of 2-octene with hydrogen peroxide.T he hierarchically structured TS-1 surpassed ac onventional nano-sized TS-1 sample in terms of alkene conversion and showed comparable selectivity to the epoxide. The flexible synthesis route described herec an be used to prepare hierarchical zeolites with improved mass transport properties for other selective oxidation reactions.