Mesoporous silica SBA

Figure 1.6 Top Low-temperature nitrogen adsorption ( ) and desorption (x) isotherms measured on a calcined SBA-15 mesoporous silica solid prepared using an EO20PO70EO20 block copolymer [54]. Bottom Pore size distribution derived from the adsorption isotherm reported at the top [54]. A high surface area (850 m2/g), a uniform distribution of cylindrical nanopores (diameter —90 A), and a large pore volume (1.17 cm3/g) were all estimated from these data. These properties make this material suitable for use as support in the preparation of high-surface-area solid catalysts. (Reproduced with permission from The American Chemical Society.)...

The SBA-15 mesoporous silica was prepared according to the work of Zhao et al. [7] by mixing tetraethoxysilane, Si(OEt)4, and the Pluronic 123 [(EO)2o(PO)7o(EO)2o] non ionic surfactant in a strongly acidic solution before hydrothermal treatment at 95°C for 72h and calcination in air at 550°C for 6h. The hexagonal P6mm symetry of the mesoporous material was confirmed with XRD [8]. Na physisorption yields a specific surface area of 720 m. g a narrow pore size distribution (15 A) with an average pore size of 64 A (BJH analysis). 

SBA-15 mesoporous silica was prepared in acidic medium using TEOS as silica source and triblock PI23 copolymer as structure directing agent [14]. After... 

CMK-2 [114] is an ordered mesoporous carbon obtained from sucrose as a source of carbon and SBA-1 silica as template [Fig. 34b)]. Electron diffraction showed that this carbon is composed of c s iirtercoimected with two different types of pores (meso- and micropores). CMK-3 [115] is an ordered mesoporous carbon that was synthesized using SBA-15 mesoporous silica as template and sucrose as carbon source. The structure of CMK-3 was the faithful replica of the mesoporous silica template, as revealed by XRD and TEM. This carbon had a hi BET surface area (1500 n g % and a pore size around 4.5 nm. The systematic control of pore wall thickness of hexagonal mesoporous silica templates (by varying the ratio of surfactants CwTAB and CmEOg, Fig. 35) afforded a close control of the... 

FIGURE 2.13 SEM images of SBA-15 mesoporous silica (a) cross-sectional view and (b) view along the pore channel direction. (From Che, S., Lund, K., Tatsumi, T., lijima, S., Joo, S.H., Ryoo, R., and Terasaki, O. Angew Chem Int Ed. 42 2182-2185, 2003. With permission.)... 

Jin ZW, Liang H (2010) Effects of morphology and structural characteristics of ordered SBA-15 mesoporous silica on release of ibuprofen. J Disper Sci Technol 31 654-659 k. Finnic mraci c chem, 1. Kong, d. Jacques, h-q. Lin, s. Mcniven, s. CaUeja, e. Gorissen And c. 

Fig. 12.4 (a) SEM cross-sectional view of a SnO sensor with a filter ( 100-nm) fabricated from SBA-15 mesoporous silica, (b) Transitory resistances of the SnO, SnO -SiO, SnOj-SiO iPd, and SnO -SiO iPt gas sensors when exposed to different concentrations of CO, from 20 to 400 ppm. Two different relative humidity conditions are considered 30-50 % (Reprinted with permission from Cabot et al. (2003). Copyright 2003 Elsevier)... 

ADSORPTION STUDIES OF SBA-15 MESOPOROUS SILICA WITH UREIDOPROPYL SURFACE GROUPS... 

Direct syntheses of ordered SBA-15 mesoporous silica containing sulfonic add groups. Chem. Mater., 12,... 

Flodstrom, K., Teixeira, C.V., Amenitsch, H., Alfredsson, V., and Linden, M. (2004) In situ synchrotron small-angle X-ray scattering/X-ray diffraction study of the formation of SBA-15 mesoporous silica. Langmuir, 20,4885-4891. 

A variety of metal triflates (M = Zn, Ce, Y, and La) have been incorporated into SBA-15 mesoporous silica [90]. The catalysts were synthesized by impregnation in an acetonitrile solution of the respective metal triflates during 8-10 h. The excess of solvent was eliminated under vacuum and later the samples were dried at 120°C. 

D. I. Margolese, J. Melero, S. C. Christiansen, B. F. Chmelka, and G. D. Stucky, 2000, Direct syntheses of ordered SBA-15 mesoporous silica containing sulfonic acid groups, Chem. Mater. 12,2448-2459... 

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