Design of functionalized fluorescent ionic liquid and its application for achieving significant improvements in Al3+ detecting

Specific fluorophore was introduced into ionic liquid based on its tunability, thus a kind of novel fluorescent ionic liquid probe [P 66614 ][HQS] was designed, synthesized and characterized. Compared with non-fluorescent HQS, ionic liquid [P 66614 ][HQS] emitted a certain amount of fluorescence, which could be attributed to the well-delocalized frontier orbitals and its charge transfer character, as demonstrated by quantum chemical calculation. Considering the interaction of [P 66614 ][HQS] with metal ions, the application for detecting specific substance as a chemical sensor, such as Al 3+ was investigated. Compared with the traditional probe HQS, significant improvements in Al 3+ detecting was achieved by [P 66614 ][HQS] with stronger binding ability, better sensitivity and selectivity. The better performance of [P 66614 ][HQS] was contributed to the changed charge distribution, leading to the stronger binding interaction. We believe that this new fluorescent ionic liquid exhibited unique properties in detecting Al 3+ in aqueous solution, which would broaden the application of ionic liquids.