Studying of 1-D assemblies in anionic azo dyes and cationic surfactants mixed systems

The construction and regulation of one-dimensional (1-D) structure have been fully investigated in anionic azo dyes and cationic surfactants mixed systems. Anionic azo dyes with different charge numbers and different size of conjugated groups were selected. Analogously, cationic alkyl quaternary ammoniums surfactants with different chain length, charges on the head, and types of the surfactants were tested. By studying the relationship between molecular structure and intermolecular interactions in a controlled way, it was found that 1-D self-assembly is a process that affected by multiple interactions, including electrostatic attractions, hydrophobic interactions, and potential π–π staking. Besides, the symmetry of the molecules also affects the morphology of the assemblies.

Combination of steric effect, π–π stacking, electrostatic and hydrophobic interaction, the packing model of dye and surfactant molecules in the 1-D nano-structures has been suggested.Figure optionsDownload as PowerPoint slideHighlights
► 1-D structures were found in azo dyes and cationic surfactants mixed systems.
► Helixes were found in one of the mixed systems.
► The regulation of the formation of these 1-D structures has been investigated.