Synthesis and properties of diphenylcarbazole triphenylethylene derivatives with aggregation-induced emission, blue light emission and high thermal stability.

New aggregation-induced emission materials derived from diphenylcarbazole triphenylethylene were prepared. The thermal, photophysical, electrochemical and aggregation-induced emissive properties were investigated. All the compounds had strong blue light emission capability and excellent thermal stability. Their maximum fluorescence emission wavelengths were between 450 to 460 nm in TLC plates, while their glass transition temperatures ranged from 162.2 to 182.4 °C. The decomposition temperatures of the synthesized compounds were all well over 500 °C. The synthesized compounds possessed aggregation-induced emission (AIE) properties, which exhibited enhanced fluorescence emissions in aggregation states or in solid states. The HOMO energy levels estimated from the oxidation potentials were found in the range from 5.49 to5.52 eV. The lowest unoccupied molecular orbital/highest occupied molecular orbital (LUMO/HOMO) energy gaps (ΔEg) for the compounds were estimated from the onset absorption wavelengths of UV absorption spectra and ranged from 3.04 to 3.20 eV.