Mesoporous Silica Synthesis: Different Precursors, Catalysts and Structure Directing Agents

8 types of silica have been synthesized by varying silica sources, catalysts and structure directing agents. All silicas were characterized by scanning electron microscopy, nitrogen sorption–desorption analysis, thermogravimetric analysis and Fourier-transform infrared spectroscopy. Silica modified with aminopropyl groups were successfully synthesized using (3-aminopropyl) triethoxysilane as a co silica source. Pluronic P123 and cetyltrimethylammonium bromide were used as structure directing agents while the P123 removal with selected solvent extraction method was partly successful. Mesoporous silica was synthesized using tetramethyl orthosilicate as a co-silica source in almost all cases while no mesopores were visible when tetraethyl orthosilicate was used as a co-silica source. Highest surface areas were achieved for silicas synthesized with urea, P123, tetramethyl orthosilicate (420 ± 2 m²/g) and tetraethyl orthosilicate (311 ± 3 m²/g), respectively. High surface area silica was also synthesized by using tetramethyl orthosilicate, (3-aminopropyl) triethoxysilane and cetyltrimethylammonium bromide (332 ± 3 m²/g). Lowest surface areas were produced by reacting P123 and (3-aminopropyl) triethoxysilane with tetramethyl and tetraethyl orthosilicates with surface areas being 9 ± 0.4 and 2 ± 0.1 m²/g, respectively.