Fluorescent conjugated microporous polymer based on perylene tetraanhydride bisimide for sensing o-nitrophenol

A novel conjugated microporous polymer based on perylene tetraanhydride bisimide (DP 2 A 2 ) has been synthesized through Sonogashira–Hagihara cross-coupling polymerization of tetrabromo-substituted perylene tetraanhydride bisimide derivative (DPBr 2 ABr 2 ) with 1,4-diethynylbenzene, whose Brunauer–Emmett–Teller (BET) specific surface area is about 378 m 2  g −1 . The fluorescence quenching behaviors of the DP 2 A 2 were investigated. It is found that the DP 2 A 2 shows high sensitivity and selectivity to tracing o-nitrophenol (o-NP) in THF with Ks V constant of 2.00 × 10 4  L mol −1 . The detection limit (LOD) is 1.50 × 10 −9  mol L −1 . The possible sensing mechanism for the luminescent quenching of DP 2 A 2 towards o-NP exciting at 365 nm was considered the donor–acceptor electron transfer mechanism, which is a combined result from both dynamic (collisional) and static quenching. Moreover, the static quenching process is dominant for DP 2 A 2 .