Branched triphenylamine luminophores: Aggregation-induced fluorescence emission, and tunable near-infrared solid-state fluorescence characteristics via external mechanical stimuli

Three AIE-active branched luminophores (defined as 4a, 4b and 4c) containing triphenylamine and carbazole units forming intramolecular charge transfer (ICT) states have been developed. The results showed that the branch number can affect effectively the performance of the tunable fluorescence in the solid state. Only compound 4a displayed a tunable solid-state fluorescence emission at near-infrared section and an obvious crystallization-induced emission enhancement (CIEE) effect with 49.8% ФF.216