Santa Barbara Amorphous-15
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![](http://upload.wikimedia.org/wikipedia/commons/thumb/6/68/SBA-15-powder.jpg/220px-SBA-15-powder.jpg)
SBA-15, an acronym for Santa Barbara Amorphous-15, is a silica-based ordered mesoporous material that was first synthesized by researchers at the university of California Santa Barbra in 1998.[1] This material proved important for scientists in various fields such as material sciences,[2] drug delivery,[3] catalysis,[4] fuel cells[5] and many other due to its desirable properties and ease of production.
Synthesis procedure
[edit]The procedure is a typical Liquid-Crystal templating that consists of three steps:
![](http://upload.wikimedia.org/wikipedia/commons/thumb/e/e7/Gel-SBA-15.jpg/220px-Gel-SBA-15.jpg)
- Solution preparation — Pluronic P123 is dissolved in an acidic solution of water at specific molar ratios[6] and the silica precursor typically TEOS or TMOS (sometimes EGMS[7]) is added and mixed in for some time.
- Hydrothermal treatment — The solution is sealed in a container and subjected to a temperature T1 for about 24 hours and then a higher temp T2 for 48 hours.
- Washing and calcination — The gel obtained from the previous step is washed with water and ethanol under centrifuging, and finally clacinated at about 550 °C for 6 hours.
Structure
[edit]The interest in SBA-15 comes from the fact that its mostly mesopoures – meaning the pores are in the range of 2 nm to 50 nm according to the IUPAC definition[8] and the fact that these pores have a well defined structure that is cylindrical shape in hexagonal ordering with their relatively thick pore walls which gives thermal stability.[9]
The sorption isotherms of these materials, demonstrate typical hysteric behavior, which is still under discussion for its causes.[2]
TEM
[edit]The transmission electron microscopy of the sample shows the cylindrical pores but also highlights then fact that the pores of this material exhibit geometric deformations.
SAXS
[edit]The small-angle X-ray scattering pattern shows typical Bragg peaks to the hexagonal structure of the material. The peak positions, is directly related to the lattice parameter.
where h and k are the miller indices.
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TEM of a typical SBA-15 sample[10]
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Demonstration of the hexagonal structure of SBA-15.
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Small angle x-ray scattering pattern of a SBA-15 sample(data from Haidar et al.)[10]
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Typical isotherm SBA-15 sample, data from Haidar et al.[10]
References
[edit]- ^ Zhao, Dongyuan; Feng, Jianglin; Huo, Qisheng; Melosh, Nicholas; Fredrickson, Glenn H.; Chmelka, Bradley F.; Stucky, Galen D. (1998-01-23). "Triblock Copolymer Syntheses of Mesoporous Silica with Periodic 50 to 300 Angstrom Pores". Science. 279 (5350): 548–552. doi:10.1126/science.279.5350.548. ISSN 0036-8075.
- ^ a b Haidar, Ali F.; Belet, Artium; Goderis, Bart; Léonard, Alexandre F.; Gommes, Cedric J. (2024-08-20). "Small-Angle Scattering Indicates Equilibrium Instead of Metastable Capillary Condensation in SBA-15 Mesoporous Silica". Langmuir. 40 (33): 17444–17453. doi:10.1021/acs.langmuir.4c01609. ISSN 0743-7463.
- ^ Song, S.-W.; Hidajat, K.; Kawi, S. (2005-10-01). "Functionalized SBA-15 Materials as Carriers for Controlled Drug Delivery: Influence of Surface Properties on Matrix−Drug Interactions". Langmuir. 21 (21): 9568–9575. doi:10.1021/la051167e. ISSN 0743-7463.
- ^ Lai, Yuan T.; Chen, Tse C.; Lan, Yi K.; Chen, Bo S.; You, Jiann H.; Yang, Chia M.; Lai, Nien C.; Wu, Jia H.; Chen, Ching S. (2014-11-07). "Pt/SBA-15 as a Highly Efficient Catalyst for Catalytic Toluene Oxidation". ACS Catalysis. 4 (11): 3824–3836. doi:10.1021/cs500733j. ISSN 2155-5435.
- ^ Chen, Taipu; Chen, Lei; Zhao, Yutong; Hao, Jinkai; Shao, Zhigang (July 2024). "Organic phosphonic acid modified SBA-15 assisted enhanced high-temperature proton exchange membrane fuel cell performance of polybenzimidazole membranes". Journal of Membrane Science. 707: 122948. doi:10.1016/j.memsci.2024.122948.
- ^ Cao, Liang; Man, Tiffany; Kruk, Michal (2009-03-24). "Synthesis of Ultra-Large-Pore SBA-15 Silica with Two-Dimensional Hexagonal Structure Using Triisopropylbenzene As Micelle Expander". Chemistry of Materials. 21 (6): 1144–1153. doi:10.1021/cm8012733. ISSN 0897-4756.
- ^ Belet, Artium; Léonard, Alexandre; Heinrichs, Benoit (2024-05-13). "Small-angle scattering and sorption data in SBA-15 materials". dataverse. doi:10.58119/ULG/L8PJJK. Retrieved 2024-05-13.
- ^ Thommes, Matthias; Kaneko, Katsumi; Neimark, Alexander V.; Olivier, James P.; Rodriguez-Reinoso, Francisco; Rouquerol, Jean; Sing, Kenneth S.W. (2015-10-01). "Physisorption of gases, with special reference to the evaluation of surface area and pore size distribution (IUPAC Technical Report)". Pure and Applied Chemistry. 87 (9–10): 1051–1069. doi:10.1515/pac-2014-1117. ISSN 1365-3075.
- ^ Chaudhary, Vasu; Sharma, Sweta (June 2017). "An overview of ordered mesoporous material SBA-15: synthesis, functionalization and application in oxidation reactions". Journal of Porous Materials. 24 (3): 741–749. doi:10.1007/s10934-016-0311-z. ISSN 1380-2224.
- ^ a b c Haidar, Ali F.; Léonard, Alexandre; Gommes, Cedric J. (2024-05-13). "Small-angle scattering and sorption data in mesoporous materials". dataverse. doi:10.58119/ULG/S0HYHL. Retrieved 2024-05-13.