| 초록 |
We herein report a novel concept of π-conjugated fluorescent molecules, 1-Cyano-trans-1,2-bis-(4’-methylbiphenyl)ethylene (CN-MBE) and its derivatives, which overcome the ‘concentration quenching’ dilemma of conventional organic fluorophores in the aggregated state. CN-MBE and its derivatives exhibit drastically enhanced fluorescence emission in the aggregated state, whereas these molecules themselves are virtually non-fluorescent in diluted solution. This phenomenon contrasts with the conventional ‘concentration quenching’ in organic fluorophores. Our systematic experiments reveal that the enhanced fluorescence emission is strongly related to the synergetic effect of the aggregation-induced planarization and the formation of J-type aggregates (restricting excimer formation), so-called aggregation-induced enhanced emission (AIEE). In addition, we have also proved that this class of AIEE fluorophores could be effectively utilized for the seminal high-performance fluorescent probes responding to the various external stimuli. |
