On the molecular basis of silica gel morphology
1M. Curie-Sklodowska Univ. Faculty of Chemistry, Department of Adsorption, M. Curie-Sklodowska Sq.3, 20031 Lublin, Poland
2M. Curie-Sklodowska Univ., Faculty of Chemistry, Analytical Laboratory, Pl. M. Curie-Sklodowskiej Sq.3, 20031 Lublin, Poland
3PQ Corporation, Research and Development Center, 280 Cedar Grove Road, Conshohocken, PA 19428 USA
Adv. Mater. Lett., 2015, 6 (1), pp 40-46
Publication Date (Web): Dec 28, 2014
Copyright © IAAM-VBRI Press
Distinction between molecular constitutions of differently made silica gels succeeded only recently. This paper seeks relationship between the different molecular structures of acid and base set gels and their morphology and pore structure. Gels were fabricated from both tetraethyl orthosilicate, TEOS, in organic solvent environment and from an economically more desirable, commercial, aqueous Na-silicate solution. When their gelling was performed in the pores of an organic resin, Amberlite, further molecular differences were observed, along with associated morphology and porosity differences. We present here unprecedented atomically resolved TEM pictures that visually prove that the molecular structures of gels deduced from their 29Si NMR and Raman spectra are real, which could also be demonstrated by computer models.
Silica gel, sodium silicate, TEOS, molecular structure, TEM, porosity.