Recyclable electropolymerized films based on donor-acceptor type AIEE-active chromophore for detecting 2,4,6-trinitrophenol

Abstract Fluorescent films were prepared based on a donor-acceptor (D-A) type aggregation-induced enhanced emission (AIEE) molecule (3B-TPA) using an electropolymerization (EP) method. The resulting poly3B-TPA films were highly sensitive and selective towards 2,4,6-trinitrophenol (TNP) in aqueous solution, with a high quenching constant of 1.19×105 M-1 and ultralow detection limit of 1.14 nM, which were attributed to a highly emissive π-skeleton and rapid exciton migration. In addition, the film fluorescence was quenched by 88.1% in 300 s after exposure to TNP vapor. This excellent performance was attributed to both Forster resonance energy transfer and photo-induced electron transfer. Significantly, the films were recycled ten times with consistent high sensitivity due to the stable cross-linked π-network and insolubility. Thus, these poly3B-TPA films might be a superior fluorescent sensor for sensing TNP, having remarkable sensitivity, selectivity, and reusability.