Hollow mesoporous silica spheres

Zhu Y, Shah NH et al (2002) Influence of thermal processing on the properties of chlorpheniramine maleate tablets containing an acrylic polymer. Phaim Dev Technol 7(4) 481-489 ZhuY, Shi J et al (2005) Stimuli-responsive controlled dmg release from a hollow mesoporous silica sphere/polyelectrolyte multilayer core-shell structure. Angew Chem Int Ed 44 5083-5087 Zhu Y, Shah NH et al (2006) Controlled release of a poorly water-soluble drug from hot-melt extrudates containing acrylic polymers. Drug Dev Ind Pharm 32 569-583... 

Fig. 18 TEM images (a, b) of hollow mesoporous silica sphere (HMS) with a 3D pore network, core-shell structure, (c) with polyelectrolyte multilayer coating as a stimuli-responsive...

Y.F. Zhu, J.L. Shi, W.H. Shen, X.P. Dong, J.W. Feng, M.L. Ruan, and Y.S. Li, Stimuli-Responsive Controlled Drug Release from a Hollow Mesoporous Silica Sphere/Polyeleclrolyte Multilayer Core-Shell Structure, Angew. Chem. Ini. Ed., 44, 5083-5087(2005). 

Figure 11.7 (a) A scheme for the preparation d) SEM images and (e and f) TEM images of of hollow mesoporous silica spheres via spon- hollow silica spheres. (Reproduced with taneous self-transformation, (b) TEM image of permission from Ref. [44], Copyright 2013, as-made mesostructured silica spheres, (c and American Chemical Society.)... 

J. (2009) Fabrication of uniform hollow mesoporous silica spheres and ellipsoids of tunable size through a facile hard-templating route. /. Mata". Chem., 19,... 

Fang, X., Chen, C., Liu, Z., Liu, P., and Zheng, N. (2011) A cationic surfrictant assisted selective etching strategy to hollow mesoporous silica spheres. 

J., Ruan, M., and Li, Y. (2005) Stimuli-responsive controlled drug release from a hollow mesoporous silica sphere/ polyelectrolyte multilayer core-shell structure. Angew. Chem., Int. Ed., 44, 5083-5087. 

Figure 32.6 Schematic diagram (a) and TEM images (b and c) of hollow mesoporous silica spheres prepared via emulsion technology assisted by CO2 gas bubbles. (Reproduced with permission from Refs [68,69].)...

Sonochemistry in synthesis Spaciousness index Sphares, silicalite Spheres, mesoporous silica Spheres, MFI, hollow Spheres, zeolite, hollow Spin echo double resonance Spinel ceramic from zeolites Spiropyrane in zeolite Y Sr exchange Sr removal Sr,K-KFl, synthesis SSZ-33 ( CON)... 

Recently, a selective etching method has been developed as a simple and effective strategy to fabricate hollow mesoporous silica particles. Fang et al. reported the formation of hollow mesoporous sihca spheres with either a wormhole-like or an oriented pore structure by treatment of sohd silica spheres in a sodium... 

Using SCF processes such as these, polymers and inorganic materials have been formed into films, fibres and spherical particles. For example, mesoporous silicate films and mesoporous silica hollow spheres have both been recently prepared using SCCO2 based technologies. ... 

The sphere synthesis has been extended into other materials. For example, mesoporous carbon capsules[285] with hollow core and mesoporous shell structures were synthesized using submicrometer-sized solid core and mesoporous-shell silica spheres as templates. 

The materials which have been mentioned here so far are predominantly shaped in planar films of hierarchical order. However, the synthesis of hierarchically structured particles is also highly desirable, as they might be further processed and used for the preparation of composite porous materials. Wu et al. showed the synthesis of raspberry-like hollow silica spheres with a hierarchically structured, porous shell, using individual PS particles as sacrificial template [134]. In another intriguing approach by Li et al. [135], mesoporous cubes and near-spherical particles (Fig. 10) were formed by controlled disassembly of a hierarchically structured colloidal crystal, which itself was fabricated via PMMA latex and nonionic surfactant templating. The two different particle types concurrently generated by this method derive from the shape of the octahedral and tetrahedral voids, which are present in the template crystal with fee lattice symmetry. 

PbS hollow nanospheres with diameters of 80-250 nm have been synthesized by a surfactant-assisted sonochemical route from Pb(CH3COO)2, thioacetamide, and sodium dodecylbenzenesulfonate [3]. 200-400 nm hollow silica spheres with mesoporous walls were prepared by the application of ultrasound to a mixture of nonionic polyoxyethylene surfactant and tetraethylorthosilicate. The presence of surface-active agents during ultrasonic synthesis was proved to be effective because surfactants can act as soft templates as well as structure directing agents for the assembly and subsequent... 

In this chapter, we provide an overview of the recent research and development in the preparation, characterization, and application of novel porous carbons using both the endotemplate and the exotemplate methods. A discussion of zeolite templates for microporous carbons is followed by that of ordered mesoporous silica templates for OMCs, nanoparticle templates for mesoporous carbons, sol-gel processed porous carbons, self-assembled colloidal crystal templates for ordered macroporous carbons, and colloidal sphere templates for hollow carbon spheres, as well as other templating approaches to preparing carbon nanostructures. Then,... 

Zhang, A., Zhang, Y., Xing, N., Hou, K., and Guo, X. (2009) Hollow silica spheres with a novel mesoporous shell perforated vertically by hexagonally arrayed cylindrical nanochannels. Chem. Mater,... 

Formation of hollow silica spheres with ordered mesoporous structure by treatment with dimethyl carbonate for selective decomposition of mesoporous silica core. Micropor. Mesopor. Mater.,... 

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