Mesoporous Siliceous Materials

Angelos S Liong M Choi E Zink JI, Mesoporous silicate materials as substrates for molecular machines and drug delivery, Chem. Eng. J., 2008, 137, 4-13. 

Immobilized CPO in the mesoporous silicate material, mesocellular foam The optimal pH at which the maximum amount of enzyme is immobilized was determined to be pH 3.4, slightly below the isoelectric point of the enzyme [12]... 

I. Honma and H.S. Zhou, Self-assembling Functional Molecules in Mesoporous Silicate Materials Optical Properties and Mesophase of Dye-doped M41S. Adv. Mater., 1998, 10, 1532-1536. 

First preliminary variants of DDM were applied in the full-profile X-ray diffraction structure analysis of a series of new silica mesoporous materials and ordered nanopipe mesostructured carbons. DDM allowed stable back-ground-independent full-profile refinement of the structure parameters of these advanced nanomaterials, a result that was unattainable by any other method. To date, DDM has been applied to many various mesoporous and mesostructured substances. The structural parameters of a series of face-centred cubic (Fm3m), body-centred cubic Im3m), and two-dimensional hexagonal (pGmm) mesoporous silicates were determined by DDM from synchrotron XRD. A comprehensive structural analysis of mesoporous silicates SBA-16 (cage-type cubic Irriim), their carbon replicas, and silica/carbon composites was performed by applying DDM. The structure of MCM-48 mesoporous silicate materials was analysed in detail by DDM from different laboratory and synchrotron XRD data. The pore wall thickness of both as-made and... 

More recently, the modified proline 21 immobilized on the mesoporous siliceous material MCM-41 was prepared, with an active site loading of0.52mmolg ... 

The first mesoporous silicate materials were developed in 1970 [134] but received little attention. Mesoporous silicas finally came to prominence when Mobil Research produced a family of hexagonally-pored silicas, MCM-41, in the early 90s [135]. Since then, many subsequent varieties have been prepared, including SBA, MSU, KIT, HMS and FSM. These materials differ in the morphology and size of their pores, e.g. SBA-15 has a hexagonal structure while MSUs have a foam-like structure. 

In 1992 scientists of the Mobil Oil Corporation published the surfactant controlled synthesis of mesoporous silicate material, designated MCM-41 [1]. Previous studies concerning the preparation and characterization [2-4] and the mechanism of MCM-41 formation [5] have been published. Based on the synthesis mechanism the idea was further developed to design mesostructured transition metal oxides analogous to the MCM-41 structure. The mechanism is based on ionic interactions of the cationic surfactant headgroups with the anionic silicate species. In the synthesis of MCM-41 related materials the charged silicate species are substituted by metal oxides which are able to form polyanions. The metal oxide polyanions perform an analogous function to the silicate species in the synthesis of MCM-41. 

Melde BJ, Johnson BJ, Charles PT (2008) Mesoporous silicate materials in sensing. Sensors 8 5202-5228 Mittal KL, Fendler EJ (eds) (1982) Solution behavior of surfactants. Plenum, New York... 

Other types of mesoporous materials have also attracted attention. For example, HMS (hexagonal mesoporous silicate) materials may be prepared with different A1 contents, similarly to common zeolites. HMS samples with an Si/Al ratio = 2.5, either in the H form or after partial exchange with Li" or Na+ cations, exhibit much less marked acidic/basic properties than comparable zeoHtes, though their chemical composition is close to that of Y zeolites [288]. Differential heats of CO2 adsorption at low coverage of 32 and 26 kJ mol were measured on the li and Na-exchanged samples respectively. This feature is ascribed to the amorphous nature of the walls, to be contrasted with the crystalline structure of zeoUtes [288]. 

Honma L, Zhou H.S. Self-assemhling functional molecules in mesoporous silicate materials Optical properties and mesophase of dye-doped M41S. Adv. Mater. 1998 10 1532-1537 Honma L, Zhou H.S., Kundu D., Endo A. Structural control of surfactant-templated hexagonal, cubic and lamellar mesoporous silicate thin films prepared by spin-casting. Adv. Mater. 2000 12 1529-1533... 

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