非掺杂型高效绿色磷光有机电致发光器件

在空穴传输层TCTA与电子传输层TPBi之间引入磷光染料Ir(ppy)3超薄发光层,制备了结构为ITO/MoO_3(2 nm)/NPB(40 nm)/TCTA(10 nm)/Ir(ppy)3(xnm)/TPBi(40 nm)/LiF(1 nm)/Al(80 nm)的非掺杂磷光有机电致发光器件。通过调控非掺杂发光层的厚度,详细研究了Ir(ppy)3层厚度对器件性能的影响。实验结果表明,当非掺杂发光层厚度为0.2 nm时,器件的性能最好,器件的亮度、效率和外量子效率分别达到26 350 cd·m~(-2)、42.9 cd·A~(-1)和12.9%。研究结果表明,采用超薄的非掺杂发光层可以简化器件结构和制备工艺,获得高效率的OLED器件。

High Efficiency Green Phosphorescent Organic Light Emitting Diodes Using An Ultrathin Nondoped Emitting Layer

The nondoped emitting layer ( EML) was constructed by introducing a ultrathin layer of pure green phosphorescent dye tris(2-phenylpyridine)iridium[Ir(ppy)3] between a hole transpor-ting layer TCTA and an electron transporting layer TPBi. The device structure is ITO/MoO3 ( 2 nm)/NPB(40 nm)/TCTA(10 nm)/Ir(ppy)3(0. 1-0. 5 nm)/TPBi(40 nm)/LiF(1 nm)/Al(80 nm) . The thickness of EML can affect the performance of green phosphorescent organic light emit-ting diodes ( PhOLEDs ) . By changing the thickness of emitting layers, the best performance of green PhOLEDs can be achieved with a 0. 2 nm pure phosphorescent dye. The device exhibits highly efficient green emission with a maximum luminance of 26 350 cd · m-2 , a maximum current effi-ciency of 42. 9 cd·A-1 and a maximum external quantum efficiency of 12. 9%. These results indi-cate that the high performance PhOLEDs can be realized with only ultrathin nondoped EMLs in a simple way.