制备了结构为ITO/NPB/TCTA/FIrpic∶TCTA/Ir(MDQ)2(acac)∶TmPyPB/FIrpic∶TmPyPB/TmPyPB/LiF/Al的有机电致磷光发光器件。通过在双蓝光发光层之间插入较薄的红光层Ir(MDQ)2(acac)∶TmPyPB调节载流子、激子在各发光层中的分布, 并结合TCTA和TmPyPB对发光层内载流子和激子的有效阻挡作用, 混合实现白光发射。研究了红光层在不同厚度、不同掺杂浓度下对器件发光性能的影响。结果表明, 红光发光层厚度为2 nm、质量浓度为5%时, 结合蓝光发光层和红光发光层, 实现了色坐标为(0.333, 0.333)、最大发光效率为11.50 cd/A的白光发射。

A novel white electrophosphorescent organic light emitting diodes (PHOLEDs) with a structure of ITO/NPB/TCTA/FIrpic∶TCTA/Ir(MDQ)2(acac)∶TmPyPB/FIrpic∶TmPyPB/TmPyPB/LiF/Al was demonstrated. The red emitting layer (Ir(MDQ)2(acac)∶TmPyPB) with different thickness and doping concentration was inserted between the double blue-emitting layers (D-BEML) to adjust the distribution of carriers and excitons. The luminescent properties of the devices were studied. The results showed that the optimum performance of OLED was achieved when the thickness of Ir(MDQ)2(acac)∶TmPyPB red emitting layer is 2 nm, and the doping mass fraction is 5%. Combining the D-BEML and the red emitting layer, WOLEDs with peak efficiencies of 11.50 cd/A and CIE coordinates of (0.333, 0.333) can be obtained.