固体润滑国家重点实验室（LSL）知识库

Thermal- and ultrasound-triggered organogels formed by an imidazolium-based salt-free catanionic surfactant 1-tetradecyl-3-methylimidazolium methyl orange [C₁₄mim][MO] in dimethyl formamide (DMF) were investigated. The [C₁₄mim][MO] organogels exhibited luminescent property owing to the aggregation-induced emission (AIE) by noncovalent interaction and displayed excellent mechanical strength and reversible sol–gel transition. Furthermore, the self-assembly behavior of [C₁₄mim][MO] in mixed solvents was also investigated. It can be observed that the addition of poor solvents (toluene, H₂O) in DMF weakened the mechanical strength of the gels. Besides, the fluorescence of gel performs opposite changes towards different kinds of solvent that the addition of solvents without benzene ring structure (ethanol and dichloromethane) reduced the fluorescence while the addition of solvents containing benzene ring structure (xylene, aniline) enhanced the fluorescence greatly owing to the π–π stacking of solvent and MO. These results reveal the important role of heat, ultrasound, and solvents in the formation of the supramolecular organogels and may help us to design new soft materials.