Hollow‐Structured Mesoporous Materials: Chemical Synthesis, Functionalization and Applications

Abstract

Hollow-structured mesoporous materials (HMMs), as a kind of mesoporous material with unique morphology, have been of great interest in the past decade because of the subtle combination of the hollow architecture with the mesoporous nanostructure. Benefitting from the merits of low density, large void space, large specific surface area, and, especially, the good biocompatibility, HMMs present promising application prospects in various fields, such as adsorption and storage, confined catalysis when catalytically active species are incorporated in the core and/or shell, controlled drug release, targeted drug delivery, and simultaneous diagnosis and therapy of cancers when the surface and/or core of the HMMs are functionalized with functional ligands and/or nanoparticles, and so on. In this review, recent progress in the design, synthesis, functionalization, and applications of hollow mesoporous materials are discussed. Two main synthetic strategies, soft-templating and hard-templating routes, are broadly sorted and described in detail. Progress in the main application aspects of HMMs, such as adsorption and storage, catalysis, and biomedicine, are also discussed in detail in this article, in terms of the unique features of the combined large void space in the core and the mesoporous network in the shell. Functionalization of the core and pore/outer surfaces with functional organic groups and/or nanoparticles, and their performance, are summarized in this article. Finally, an outlook of their prospects and challenges in terms of their controlled synthesis and scaled application is presented.

Design Advances in Particulate Systems for Biomedical Applications

“…[ 204,205 ] The simplest structures are hollow mesoporous particles combining a large void space in the core and the mesoporous network in the shell (one compartment) - Figure 20 .…”

“…Reproduced with permission. [ 204 ] Copyright 2014, John Wiley and Sons. Aluminosilicate treated with 3-aminopropyltriethoxysilane Ibuprofen Improved capacity to storage the drug.…”

Ultrasensitive Luminescent In Vitro Detection for Tumor Markers Based on Inorganic Lanthanide Nano‐Bioprobes

“…Besides the direct bioconjugation through ligand‐free synthesis, chemical bonding between the functional groups on the surface of inorganic Ln 3+ ‐NPs (e.g., maleimide, thiol, carboxylic, aldehyde, and amine) and those of the biomolecules are most prevalent for the bioconjugation of Ln 3+ ‐NPs 21. Cross‐linking reagents such as ethyl(dimethylaminopropyl) carbodiimide (EDC) and N‐hydroxysuccinimide (NHS), o ‐benzotriazole‐ N,N,N′,N′ ‐tetramethyluronium‐hexafluoro‐phosphate (HBTU) and N,N ‐diisopropylethy (DIEA), dicyclohexylcarbodiimide (DCC) and 1‐hydroxybenzotriazole (HOBT) have been employed to activate the functional groups of biomolecules (Figures 3c and 3d).…”

Synthesis and Characterization of Nontoxic Hollow Iron Oxide (α-Fe2O

“…The parameters such as size, shape, and structure can influence the physical and chemical properties of the NPs [1]. The properties such as high surface area, monodispersity in the particle size, open and low density structures, optical properties, and nontoxic behaviour are making them an important class of nanomaterials [2,3].…”

“…Template methods are most effective in the formation of hollow structures in accordance with the uniformity [10]. These procedures are expensive and include many steps for the synthesis as well as for the removal of templates that often lead to the breakage of hollow sphere while template is removed [2,11,12]. So there is a need of simple, straight forward, and cost effective solution based approaches for the synthesis of hollow iron oxide NPs although there have been many reports on solution based 2 Journal of Nanomaterials synthesis of uniform hollow nanostructures [13].…”