| Abstract
| - We compare how (i) four ionic liquids (ILs) (1-butyl-3-methylimidazolium tetrafluoroborate ([C4mim][BF4]), 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C4mim][Tf2N]), 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([C4mpy][Tf2N]), and trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)imide([P(C6)3C14][Tf2N])) and (ii) two conventional molecular liquids (methanol and 1-octanol) solvate/wet luminescentorganic moieties that are covalently attached to the surface of silica controlled pore glass (CPG). A series of aminopropylCPG particles that have been covalently tagged with the solvatochromic fluorescent probe group dansyl were usedin this study. The results demonstrate that ILs solvate/wet the silica surface differently in comparison to molecularliquids (MLs). Specifically, when comparing ILs and MLs that appear to solvate the free probe, dansylpropylsulfonamide(DPSA), equally in solution, we find that ILs do not solvate/wet the silica surfaces as well as the corresponding MLs.The cation component in these ILs is the significant factor in how the ILs solvate/wet silica surfaces. Solvation/wettingof surface-bound species at a silica surface depends on the cation size. Chlorosilane end-capping of the surface silanoland amine residues attenuates the cation's affects.
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