Imidazolium ionic liquids as bifunctional materials (morphology controller and pre-catalyst) for the preparation of xerogel silica’s

• Published in: Journal of sol-gel science and technology 2008-12, Vol.48 (3), p.272-276
• Main Authors: Migliorini, Marcelo V., Donato, Ricardo K., Benvegnú, Moisés A., Gonçalves, Reinaldo S., Schrekker, Henri S.
• Format: Article
• Language: English
• Subjects: Catalysis; Catalysts; Ceramics; Chemistry; Chemistry and Materials Science; Colloidal gels. Colloidal sols; Colloidal state and disperse state; Composites; Controllers; Exact sciences and technology; Fast Track Communication; Flat surfaces; General and physical chemistry; Glass; Inorganic Chemistry; Ionic liquids; Ions; Materials Science; Morphology; Nanotechnology; Natural Materials; Optical and Electronic Materials; Photography; Scanning electron microscopy; Silicon dioxide; Sol-gel processes; Solvents; Tetraethyl orthosilicate; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Thermogravimetric analysis; Triethylene glycol; X ray powder diffraction; X-ray diffraction; Xerogels
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-008-1820-2

This article describes the preparation of xerogel silica’s by the sol–gel technique in the presence of the ionic liquids (ILs) 1-triethylene glycol monomethyl ether-3-methylimidazolium methanesulfonate 1 and 1-monoethylene glycol monomethyl ether-3-methylimidazolium methanesulfonate 2 , using tetraethoxysilane as precursor. The addition of water to these ILs resulted in the formation of protonic acid. As a consequence, the ILs functioned as morphology controller and acid pre-catalyst at the same time. Characterization of these materials was performed by photography, scanning electron microscopy, thermogravimetric analysis and powder X-ray diffraction. Compact lamellar monoliths with interlamellar distances of approximately 1.5 nm and flat surfaces were obtained with both ILs.