Tetraphenylethylene-based fluorescent conjugated microporous polymers for fluorescent sensing trinitrophenol

Two tetraphenylethylene-based fluorescent conjugated microporous polymers (TTTPT and TTDAT) were obtained by the Friedel−Crafts polymerization reactions catalysed by CH3SO3H. In virtue of containing tetraphenylethylene, triphenylamine and s-triazine units in their porous skeletons, the resulting TTTPT and TTDAT show excellent fluorescence sensing performance for trinitrophenol (TNP) with high quenching coefficients of 1.66 × 104 and 1.31 × 105 l mol–1, respectively. TTDAT can also sense to dinitrophenol (DNP) with the Ksv of 2.70 × 104 l mol–1. The fluorescent quenching mechanisms of TTTPT and TTDAT for selective detecting TNP attribute to conventional photoinduced electron-transfer mechanism, absorption competition quenching mechanism and/or the resonant energy transfer mechanism.