Schiff base modified α-cyanostilbene derivative with aggregation-induced emission enhancement characteristics for Hg2+ detection

A Schiff base functionalized α-cyanostilbene derivative (TS) has been synthesized via a simple and straightforward method and characterized by FT-IR, 1H NMR, 13C NMR and mass spectra. TS possessed excellent AIEE properties and exhibited “turn-on” fluorescent responses to Hg2+. The results of UV–vis and fluorescence titration experiments revealed that TS was selective and sensitive to Hg2+ in pure THF and aqueous environment. The coordination of TS and Hg2+ ions generated TS–Hg complex locked the “dancing molecule” because of the flexible chain in the middle of the molecule and the complex was lower soluble induced formation of large aggregates that further limited the non-radiative relaxation channel enhanced emission after adding Hg2+ ions in aqueous solution, which had been confirmed by 1H NMR and dynamic light scattering (DLS).