Gelation and fluorescent organogels of a complex of perylenetetracarboxylic tetraacid with cationic surfactants

In the work we report the formation of fluorescent organogels in toluene of a complex of perylenetetracarboxylic tetraacid (PTCTA) with four cationic surfactants. We found that the gel formation is a function of the gelation temperature and solution concentration. The TEM characterization indicates twisted- or straight-belt aggregates formed in gel-phase or in crystals. The further XRD characterization illustrated a layered structure of complex molecules in these aggregates, mainly driven by π–π stacking of the rigid perylene cores. The UV/vis and fluorescence spectra show the H-type aggregates in the gel-phase. The changes of the aggregate morphology and molecular packing structures with the gelation temperature and solution concentration reflect a competition between gelation and crystallization under the conditions used and the details are discussed in text.