为了克服现有的以玻璃为基底、ITO为电极的有机电致发光器件(OLED)的韧性差、对裂纹缺陷敏感等固有缺点, 对现有的OLED器件结构进行优化。本文提出了以PET为基底, 旋涂高导PEDOT∶PSS作为阳极的高效柔性OLED器件结构。并在此基础上, 通过纳米压印蛾眼模板将光耦合结构引入器件, 提高器件的光取出效率。此绿光FOLED器件在亮度为1 000 cd·m-2时, 功率效率为36.10 lm·W-1。在此基础上, 通过纳米压印引入光耦合结构的柔性OLED器件表现出良好的光电性质, 在亮度为1 000 cd·m-2时, 功率效率可达到80.46 lm·W-1。并且这种绿光柔性OLED器件在以器件半边长为曲率半径180°弯折200次后亮度衰减很少。此种高导PEDOT∶PSS电极和柔性PET基底可以成为较好的ITO透明电极和刚性玻璃基底的替代物, 为生产可穿戴式设备提供了可能。

Flexible organic light emitting diodes (FOLEDs) have attracted an amount of attentions due to their advantages in power-consumption and color-quality for lighting and display applications. Although the indium-tin-oxide (ITO)-coated glass substrates are widely used in OLEDs, their brittle nature limits the further development of flexible OLEDs for some special products. Here, we present a device structure which uses plastic PET as the substrate and spin-coated high-conductivity PEDOT∶PSS as the anode. Based on this OLED device structure, Moth’s eye nanostructure is imprinted on OLED to introduce optical outcoupling structure and increase the light outcoupling efficiency. The green flexible OLEDs on this substrate exhibit superior optical and electrical characteristics, showing a power efficiency of 36.10 lm·W-1 at 1 000 cd·m-2. By introducing a nanoimprinted light-outcoupling structure on the PET film, flexible OLEDs can yield a power efficiency of 80.46 lm·W-1 at 1 000 cd·m-2 with excellent optical and electrical characteristics. In the bending tests, the FOLEDs show great mechanical stability in luminance after bending 200 cycles in 180°. It is demonstrated that the PET-PEDOT∶PSS substrate of the flexible OLED can work as an alternative for the counterpart on ITO-glass substrate for the use in wearable and mobile communication devices.