Cu(I)-Luminophore für die OLED-Anwendung - Effiziente Emitter mit thermisch-aktivierter verzögerter Fluoreszenz (TADF) und kombinierter Emission

The present work includes the synthesis and investigation of new OLED emitter materials based on Cu(I). With the specific modification of different parameters and a consequent development a series of highly efficient, neutral sublimable Cu(I) halide emitter materials could be created. With quantum yields ΦPL of 89 % in powder and 56 % in PMMA matrix these compounds not only number among the most efficient Cu(I) halide emitters to date, but also the processability via sublimation makes them a potential candidate for OLED application. With the rational development and optimization of the complex system [Cu(tpyz)(PPh3)]PF6, invented by GNEUSS et al., a series of highly efficient cationic Cu(I) emitter materials could be generated. These outstanding Cu(I) emitter materials exhibit quantum yields ΦPL of up to 95 % in powder, up to 84 % in PMMA matrix and up to 76 % in solution, making them currently the best overall emitter systems. Especially the high quantum yields ΦPL coupled with combined emission properties and short life times of the excited states reveal the high potential of this emitter system for application in OLED technology. Moreover, its high variability regarding the tuning of emission colors by changing the monodentate ligand enable the generation of efficient emitter materials from the deep-blue to the yellow area of visible light with quantum yields > 60 %. A further development and completion of this emitter system should involve the preparation of emitter materials with luminescence in the red area of light. This could be managed by exchange of the established tripod ligands tpypo and tpym by electron poor derivatives. Electron poor derivatives could be obtained by using fluorinated pyridine derivatives or pyridines with larger conjugated π-systems like quinoline derivatives.