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structured zeolites, with the main focus on the synthesis strategies that are available, with examples given from the literature. Available approaches are reviewed for the preparation of micro-mesoporous structured zeolites, micro-macroporous structured zeolites and micro-meso-macroporous structured zeolites. Furthermore, the enhanced mass transport properties of hierarchically structured zeolites, featuring additional larger pores in addition to the crystalline micropores, have also been described. The significant improvement in catalytic properties in a range of important reactions resulting from enhanced mass transport properties have also been discussed through several representative cases. It is the intent of this work to stimulate intuition into the optimal design of related hierarchically organized zeolites with desired characteristics.

Monodisperse and high-surface-area mesoporous inorganic spheres of various compositions including metal oxides, mixed oxides, and metal phosphates are prepared by templating mesoporous carbon spheres which are replicated from spherical mesoporous silica. Due to the rigid and thermally stable framework of carbon template, the crystalline phases of the obtained metal oxide spheres can be readily tailored by controlling crystalline temperatures. Moreover, the sphere morphologies can be changed from solid structure to hollow structure in some cases by changing the polarity of the precursor, due to the hydrophobic nature of carbon template.

Zeolitic wood structures made by a seeded templating process offer new ways of investigating the complex wood morphology. The technique can also be used to create hierarchical porous zeolitic materials (see Figure). The seeded growth strategy shows potential for the extension to any organisms with hierarchical structure and might make multilevel porous zeolites of other types feasible.

Hollow capsules have recently attracted much attention because their unusual properties may find wide potential applications in chemistry, biotechnology, and materials science.

Mesostructured silica MCM-41 has been one of the most extensively studied mesostructured materials since its first synthesis by Mobil scientists in 1992.[1] Many important applications [2] of mesostructured silica MCM-41 in catalysis, separation, and nanoengineering are closely correlated to its ordered two-dimensional (2D) hexagonal mesostructure/ mesopore. Besides the usual straight 2D hexagonal mesostructure, [3] various curved mesostructures of MCM-41 have also been reported by several research groups in the last decade, [4] which has aroused great academic interest in their enigmatic morphogenesis. Recently our research group has investigated the topological transformation of a series of vesicular MCM-41 compounds with different mesostructures in an alkaline synthesis system [5] that was initialy developed by Rathouský and co-workers.[6] The self-assembly of sodium silicate (SS) and cetyltrimethylammonium bromide (CTAB) into a hexagonal mesostructure in such a method is driven by the hydrolysis of ethyl acetate (EA). Herein we report that chiral mesostructured silica nanofibers of MCM-41 can be fabricated in this SS/CTAB/EA/H 2 O system by simply lowering the SS and CTAB concentrations below 0.5 mol per 1000 mol H 2 O. It is remarkable that two types of chiral mesostructures with different symmetries were synthesized from the usual achiral materials in this study. Moreover, a relationship between the chiral and ordinary achiral mesostructures of MCM-41 was revealed through a systematic investigation of the synthesis system.The first type of chiral nanofibers of MCM-41 (Figure 1 a, b) has a single twist axis. The XRD pattern of such a single-axis nanofiber (Figure 1 c) reveals a highly ordered 2D hexagonal mesostructure with a lattice constant of 4.5 nm. The N 2 sorption isotherms of the calcined product show a steep capillary condensation at a P/P 0 ratio of 0.2:1-0.3:1, which corresponds to a BJH pore size of 2.4 nm (Figure 1 d). The BET surface area and mesopore volume of the single-axis nanofiber are 960 m 2 g À1 and 0.63 cm 3 g À1 , respectively. Analysis of the chiral mesostructure of the single-axis nanofibers by electron microscopy showed: 1) The twisted crystal facets could be distinguished from their field-emission SEM images (see Supporting Information); 2) periodic fringes along the axis of the nanofiber in the TEM image (Figure 1 b); and 3) the observed fringes moved along the axis when the

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A novel and flexible strategy involving hydrothermal transformation of guest‐incorporated zeolite‐seeded mesoporous silica spheres was proposed to prepare guest‐encapsulated hollow zeolite spheres and three‐dimensionally (3D) ordered macroporous zeolite monoliths. The guest species that were pre‐incorporated into the mesopores of silica spheres could be spontaneously encapsulated inside the formed hollow zeolite shells by consuming silica nutrition of the original mesoporous silica cores during the hydrothermal process. A wide range of guest materials with a size ranging from nanometers to micrometers, e.g., Ag and PdO nanoparticles, and mesoporous spheres of carbon and polymer of micrometer size were successfully encapsulated into both discrete hollow zeolite spheres and 3D ordered macroporous zeolite monoliths. Such materials are expected to find a variety of applications such as catalysis, adsorption, and novel microreactors for their special structures with active species inside and zeolitic porous shell outside.