Fluorinated surfactant templating of vinyl-functionalized nanoporous silica

Ordered nanoporous vinyl-functionalized silica materials are synthesized by the 'one-pot' (direct) synthesis method using three cationic fluorinated surfactants (C₆F₁₃C₂H₄NC ₅H₅Cl, C₈F₁₇C₂H ₄NC₅H₅Cl and C₁₀F₂₁C ₂H₄NC₅H₅Cl) as templates in basic medium under ambient conditions. The materials obtained possess lower degrees of 2D hexagonal closed packed ordering of the pores when compared to CTAB templated materials. Increases in vinyl content lead to reductions in pore size as well as material order. In spite of having smaller pores, bromination experiments suggest that the vinyl groups are more accessible in the fluoro-surfactant templated materials. Although confinement of the vinyl groups to the palisade region of the fluorinated micelle templates may contribute to this increase in accessibility, reduced pore order in the fluorinated templated materials may also improve the accessibility, as observed here for intentionally disordered CTAB-templated materials. Cationic fluorocarbon surfactants not only have the potential to be templating agents, but also present the possibility of re-organizing the alignment of organic functional groups in the pores of organic-inorganic hybrids obtained by direct synthesis.