Luminescent nanofibers fabricated from triphenylvinyl substituted carbazole derivatives via organogelation for sensing gaseous nitroaromatics

Abstract

New triphenylvinyl substituted carbazole derivatives TPEICE, TPEC and TPECBr have been synthesized. They could self-assemble into nanofibers via organogelation processes in some organic solvents. Notably, the obtained xerogel-based films could emit strong fluorescence although the three compounds were non-emissive in solutions, indicating AIE in gel phases. The emission of TPEICE and TPEC in xerogel-based films could be quenched significantly upon exposed to gaseous DNT and TNT, while TPECBr could not sense nitro compounds on account of its poor electron donating ability. We also found that reversibility of the fluorescence response of TPEC was better than TPEICE because the photo-induced electron transfer would happen during the recognition of nitroaromatics for TPEICE and TPEC, except for the formation of charge–transfer complex between TPEICE and nitro compounds. Therefore, the different fluorescence response behaviors of TPEICE, TPEC and TPECBr towards nitroaromatics were resulted from their different electron donating abilities.