在有机电致发光器件中插入金属超薄层常会带来一些意想不到的作用。 在无机材料MoO3与有机材料TPD之间插入5 nm金属层Au, 制备了结构为ITO/MoO3(5 nm)/Au(5 nm)/TPD/AlQ/LiF/Al的OLED器件。 相对于没有金属层Au的器件, 发光效率得到了提高。 通过分析认为Au在TPD和MoO3之间形成一个小的空穴陷阱, 在降低了器件中的电流密度的同时, 由于5nm的Au对AlQ绿光的光透过率大于80%, 发光亮度未受明显影响, 是发光效率提高的原因。 本文为提高OLED器件发光效率提供了新的思路和实验依据。

Inserting metal thin layer into organic electroluminescent device often brings some unexpected effect. By inserting 5 nm Au thin layer between MoO3 and TPD, we prepared the OLED device with the structure of ITO/MoO3(5 nm)/Au(5 nm)/TPD/AlQ/LiF/Al. The luminous efficiency is improved as compared to the device without the Au. By analysis, we believe that the Au between MoO3 and TPD formed a small trap for hole to reduce the current density in device. At the same time, since the light transmittance of green light (AlQ) of 5 nm Au is greater than 80%, the brightness of the device was not significantly affected. That is the reasons for the improved luminous efficiency. This work provides some new ideas and experimental evidence for how to improve the luminous efficiency of OLED devices.