两种蓝色有机电致发光材料

Two Kinds of Blue Organic Light Emitting Materials

重点研究以两种蓝色OEL材料蒽类衍生物JBEM和联苯乙烯衍生物DPVBi分别作基质,以perylene作掺杂剂的器件的电致发光性能,特别研究了它们的稳定性。在亮度和效率方面,两种器件并没有很大差别,然而在稳定性方面却有很大差别,蒽类衍生物JBEM的器件在100cd/m2初始亮度下,半亮度寿命可达1035h,而DPVBi的器件在同样条件下,半亮度寿命为255h。通过分析两种器件的能级图,认为稳定性的差别可能源于两种蓝光材料本身的热稳定性不同,JBEM优于DPVBi,是一种很有前途的蓝色发光材料。

Two kinds of blue OLEDs with the structure ITO/CuPc/NPB/JBEM: perylene/Alq/Mg:Ag [Device(J)] and ITO/CuPc/NPB/DPVBi:perylene/Alq/Mg:Ag[Device(D)] were studied.The maximum luminance were 7 526cd/m2 and 6 123cd/m2, maximum luminous efficiency were 1.45 lm/W and 0.83 1m/ W for Device(J) and Device(D), respectively. The difference of luminance and efficiency was not obvious for the two devices. However, there was remarkable difference for their lifetime. The Device(J) achieved the longer halflife of 1 035h at initial luminance of 100cd/m2, and that of Device(D) was only 255h. According to their energy level diagrams, the difference of stability may originate from light emitting materials in the two devices. It may be attributed to the higher thermal stability of JBEM molecules than that of DPVBi. JBEM may be a promising blue organic light emitting materials.