Synthesis of highly ordered mesoporous hybrid silica from aromatic fluorinated organosilane precursors

Organo-fluorinated mesoporous MCM-41 type silica presenting a high degree of order has been prepared from co-condensation of tetraethoxysilane (TEOS) and pentafluorophenyltriethoxysilane [PFPTES (1)] in the presence of cetyltrimethylammonium bromide as a template. Both basic and acidic routes have been explored. In the presence of an excess of water using fluoro-precursor (1), most of the bound fluoro-organic moieties are cleaved, yielding to pentafluorophenyl doped silica. Higher fluorine content silica-based MCM-41 materials were obtained by using 2-pentafluorophenylethyltriethoxysilane [PFPETES (2)] as the organosilane precursor. In that case, the fluoro-containing groups remain covalently bound to the mesoporous inorganic network, yielding materials with potential hydrophobic, adsorbing and optical properties.