Multiple-Stimuli Responsive Luminescent Gels Based on Cholesterol Containing Benzothiadiazole Fluorophores

Two new fluorescent organogelators based on cholesterol containing benzothiadiazole group have been designed and synthesized. Three methods for gels preparation have been presented, such as heating-cooling process, ultrasonic treatment and mixed solvents under room temperature. For both of the gels, their states and emission colors exhibit striking changes upon addition of Hg²⁺. The gelation properties, structural characteristics and fluorescence of the gels were studied by FT-IR, UV-Vis absorption and PL spectra. The underlying mechanism of gelation property was studied by X-ray diffraction combined with theoretical calculation, and the important role of π- π interactions in forming the gels has been proved.