Pillararene-Based Aggregation-Induced-Emission-Active Supramolecular System for Simultaneous Detection and Removal of Mercury(II) in Water

Supramolecular polymers are polymers based on monomeric units held together with directional and reversible noncovalent interactions. Compared with traditional polymers, they possess better processability and better recycling properties, owing to their reversible monomer-to-polymer transition. Herein, we report the construction of a new supramolecular system through self-assembly of a thymine-substituted copillar[S]arene 1 and a tetraphenylethylene (TPE) derivative 2 in the presence of Hg2+. Copillar[S]arene 1 can. coordinate with Hg2+ tightly through T-Hg2+-T pairings. On the other-hand, 1 can bind with guest molecule 2 through host guest interactions-between the pillararene catty and the nitrile moiety of 2. These joint interactions generte crisscrossed networks composed of 1, 2, and Hg2+, which eventually Wrap into spherical narioparticles. Due to the aggregation-induced emission (AIE) properties of 2, the formed supramolecular polymer exhibits strong fluorescence which renders convenient the detection of the Rg(2+)-containing nanoparticles and the subsequent removal procedure. Furthermore, the polymer precipitate can be readily isolated by simple treatment, and the pseudorotaxane 2 subset of 1 can be recycled and reused. Our study has demonstrated a practical strategy for the sensing and removal of heavy metal ions in water by the construction of supramolecular polymers,.