(t-bt)2Ir(acac)超薄层厚度对有机电致发光器件性能的影响

以新型铱配合物黄光磷光染料bis2-(4-tertbutylphenyl)benzothiazolato-N,C2']iridium(acetylacetonate)(tbt)2Ir(acac)]为超薄层,制备了结构为indium tin oxide(ITO)/N,N'-bis(naphthalen-1-yl)-N...

Effects of ultrathin layer thickness of iridium complex phosphor (t-bt)_2Ir(acac) on the performance of organic light emitting devices

Using a novel yellow iridium complex phosphorescent dye of bis2-(4-tertbutylphenyl)benzothiazolato-N,C2′] iridium(acetylacetonate) (t-bt)2Ir(acac)] as the ultrathin layer,organic light-emitting devices(OLEDs) are fabricated with a structure of indium tin oxide(ITO)/ N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-benzidine(NPB)(45 nm)/(t-bt)2Ir(acac)(d)/ NPB(5 nm)/2,2′,2′′(1,3,5-benzenetriyl) tris-(1-phenyl-1H-benzimidazole)(TPBI)(30 nm)/Mg:Ag(200 nm).By changing the thickness of the ultrathin phosphor layer,the OLED properties influenced by the thickness are investigated.The results show that the device with a 0.2-nm-thick phosphor layer has a maximum brightness of 18 400 cd/m2.and the white light emission is obtained with commission internationale de l′Eclairage(CIE) coordinates of(0.33,0.32) at a bias of 6 V.The device with a 0.1-nm-thick phosphor layer has the highest power efficiency of 5.4 lm/W.The analysis indicates that the high performance results from both the direct carriers trapping of phosphor dye to confine the complex emission zone as well as an effective energy transfer from NPB to the phosphor dye.