Naslov
Crystallisation of intermediate complexes for controlling of hydrolysis rate and network morphology in the course of the sol-gel process

Autori
Mandić, Vilko ; Kurajica, Stanislav

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book Of Abstracts Aerogels 2020 / Garcia Gonzales, Carlos - Santiago de Compostela, 2020, 1-1

Skup
International Conference on Aerogels for Biomedical and Environmental Applications

Mjesto i datum
Santiago de Compostela, Španjolska, 18.02.2020. - 20.02.2020

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Morphology, Structure, Complexation, Sol-gel, Aluminium sec butoxide, Ethyl acetoacetate, PXRD, Alumina

Sažetak
In the course of the preparation of extremely porous materials such as aerogels, a non-destructive removal of the liquid media, i.e. solvent necessary for the growth of the porous materials in the first place, is the bottleneck step as normally it cannot be performed successfully at ambient conditions. However, the obtaining and the properties of the porous material can be tailored as well. While porogens can be used, a sol-gel reaction can also be employed to tailor the formation of porous network. The process may be influenced and controlled by selection of the precursors, normally alkoxides with different branching levels, but also equally important by influencing of the hydrolysis and polycondensation stages. In addition, variety of alkoxides are not available for systems other than silica, so control of hydrolysis and polycondensation becomes increasingly important in preparing of alumina nanomaterials. Control over the abovementioned processes is gained by the addition of complexation agent that reduces the activity of reactive sites by means of chemical shielding. Thereof, in the course of the sol-gel reaction, multiple oligomers may be formed with different stabilities. Analysis of crystallised compounds would ease up the understanding of the formation mechanisms and stabilities in the complex chelates systems. For the purpose, the best way would be to derive a mono crystal and conduct structural analysis. In this work, the structural analysis of polycrystalline chelate sample has been conducted, and previously undescribed crystal phase (AlEAA3) was described. Here a monocrystal could not be synthesised, but modern computational performance enabled solving of the structure. Monoclinic AlEAA3 crystallizes in P21/n space group.

Izvorni jezik
Engleski

Znanstvena područja
Kemija, Kemijsko inženjerstvo, Interdisciplinarne tehničke znanosti

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