Publications

Hierarchically organized silica monoliths

Author(s)
Sylvia Flaig, Johanna Akbarzadeh, Herwig Peterlik, Nicola Huesing
Abstract

The influence of different acids, such as hydrochloric acid, sulfuric acid, nitric acid, hydrobromic acid and acetic acid on the polymerization-induced phase separation process in the formation of hierarchically organized silica monoliths was investigated in detail. Special emphasis is given to systems synthesized from tetrakis(2-hydroxyethoxy)silane (EGMS) or tetramethoxysilane (TMOS) as the silica source in the presence of Pluronic(A (R)) P123 serving as structure-directing agent. The obtained silica monoliths exhibited a co-continuous and cellular macroporous structure comprising 2D hexagonally arranged mesopores with high specific surface areas ranging from 320-787 m(2) g(-1) independent of the applied silane precursor and regardless whether hydrochloric acid or sulfuric acid was used. A drastic change in macropore morphology to closed pores or particulate structures was observed for nitric, bromic as well as acetic acid. For sulfuric and nitric acid, the influence on the mesostructure was not as pronounced and 2D hexagonally arranged mesopores were obtained. With bromic and acetic acid a loss in mesopore ordering has been observed. Best developed hierarchically organized networks with respect to a co-continuous, cellular macroporous network, specific surface area and 2D hexagonally arranged mesopores were obtained for EGMS as well as for TMOS with P123 in sulfuric acid.

Organisation(s)
Dynamics of Condensed Systems
External organisation(s)
Paris-Lodron Universität Salzburg
Journal
Journal of Sol-Gel Science and Technology
Volume
73
Pages
103-111
No. of pages
9
ISSN
0928-0707
DOI
https://doi.org/10.1007/s10971-014-3500-8
Publication date
01-2015
Peer reviewed
Yes
Austrian Fields of Science 2012
103020 Surface physics, 103018 Materials physics
Keywords
ASJC Scopus subject areas
Electronic, Optical and Magnetic Materials, Condensed Matter Physics, Ceramics and Composites, Materials Chemistry, Chemistry(all), Biomaterials
Portal url
https://ucris.univie.ac.at/portal/en/publications/hierarchically-organized-silica-monoliths(7073d095-08a9-4dce-b579-023d02682c32).html