| Abstract
| - Fluorocarbon-functionalized mesoporous silica is synthesized by the co-condensation of tetraalkoxysilaneand fluoro-functionalized alkoxysilane precursors using a cationic fluorocarbon surfactant, C6F13C2H2NC5H5Cl (HFOPC) and C8F17C2H2NC5H5Cl (HFDePC), or a traditional hydrocarbon surfactant (C16H33N(CH3)3Br,CTAB) as templates. Fluorocarbon functionalization decreases the silica pore order, pore size, and surfacearea. The chain length of the fluorocarbon functional precursor and the surfactant template affects the poreorder, the materials textural properties, and the fluorocarbon incorporation. Matching a fluorocarbon surfactantwith a fluorocarbon functional precursor does not improve functional group incorporation; the incorporationof the perfluoro-octyl functional group is greater in CTAB-templated silica than in HFOPC-templated silica.The application of these mesoporous silica powders to fluorous separations is demonstrated using hydrocarbonand fluorocarbon-tagged anthraquinones. Dye elution through a packed column of mesoporous silica occursin a narrower band than that for fluorocarbon-functionalized silica gel, consistent with the high fluorocarboncontent and smaller pore and particle sizes of the mesoporous material.
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