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
The procedure is a typical Liquid-Crystal templating that consists of three steps:
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
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
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.
^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 cHaidar, 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.