文摘
Aggregation induced emission (AIE) is an amazing property for light emitting materials and has attractedmuch attention. Here, we report a new kind of AIE materials: fluorenone derivates 2,7-dip-tolyl-fluorenone(DTFO) and 2,7-bis(4-(tert-butylthio)phenyl)-fluorenone (DSFO). Strong light emissions with a large Stokesshift and long lifetime in the solid state originate from the formation of excimers. The crystal structure ofDSFO shows that every two molecules are bound together even in the ground state by intermolecular hydrogenbonds and form a particular dimer. When this dimer is excited, it turns into an excimer without arrangementadjustment and likewise without repulsive interactions when the excimer decays back to the dimer; so, thenonradiative decay pathways that exist in common excimers are greatly reduced and thus induce a stronglyenhanced luminescence in the solid state. OLED devices employing DTFO as light emitting layers are fabricatedand evaluated.