Synthesis of spherical mesoporous silica - A study on the influence of shake speed and synthesis gel temperature

Full text: Mesoporous silicas have attracted much attention since their discovery and this is due to its interesting properties such as high surface area, tunable pore size and easy functionalization [1]. Mesoporous silica structures have growing importance as support for enzymes and molecular organometallic catalysts [2]. The objective of this work was to synthesize ordered mesoporous materials of silica with different morphology, from the change of basic synthesis standards such as temperature and agitation. Synthesis of the material SBA-15 and KIT-6 was made where from the stirring and temperature changes it was possible to obtain spherical morphology for both materials that were also synthesized by the conventional method for comparative purposes. The materials resulting from the syntheses were discussed by means of X-ray diffraction (XRD), where the organization and internal spacing of the material were observed from scanning planes, Scanning Microscopy (SEM) to observe and confirm the formation of morphology and finally adsorption and Desorption of N2 where we can observe the distribution and homogeneity of the mesopores formed in the materials. It was observed that the change in morphology affected the internal organization of the pores for the SBA-15 material in a more significant way whereas the KIT-6 material presented little change in this sense. The pore volume was also affected for both materials where for SBA-15 we had a decrease and for KIT-6 an increase. The morphological change by this method showed that KIT-6 showed a better performance in comparison to SBA-15. [1] E. D. Mohamed Isa, I. S. Mahmud, H. Ahmad, and M. B. Abdul Rahman. Ceram. Int., vol. 45, pp. 12149–12153, 2019. [2] W. Zhang, S. Li, J. Zhang, Z. Zhang, and F. Dang. Microporous Mesoporous Mater., vol. 282, pp. 15–21, 2019. (author)