Considering a device structure consisting of multi-stacked layers with different refractive indices, we proposed a composite electrode to diminish total internal reflection, thereby improving the out-coupling efficiency of organic light-emitting diodes (OLEDs). The selected transparent conducting oxide materials for the composite electrode were composed of the same main material, gallium-doped zinc oxide (GZO), to avoid lattice mismatch and reduce interfacial strain. Herein, silicon-doped GZO (SGZO) with a relatively low refractive index was used in combination with molybdenum-doped GZO (MGZO) with a high work function to form a multifunctional transparent composite electrode. High transmittance of 94.5% and adequate sheet resistance of 52.3 Ohm/sq were realized through the design of SGZO/MGZO films on a glass substrate. The tested blue phosphorescent OLEDs with SGZO/MGZO composite anode outperformed devices with other selected single-layer electrodes, achieving a high peak efficiency of 29.0% (57.6 cd/A and 47.6 lm/W). These results demonstrate clear advantages of using this composite-electrode concept for realizing high efficiency OLEDs or other flexible optoelectronics.

考虑到由具有不同折射率的多层堆叠组成的器件结构，我们提出了一种复合电极来减少全内反射，从而提高有机发光二极管（OLED）的输出耦合效率。所选择的用于复合电极的透明导电氧化物材料由相同的主要材料掺杂镓的氧化锌（GZO）组成，以避免晶格失配并减小界面应变。在此，将折射率较低的硅掺杂的GZO（SGZO）与功函数高的钼掺杂的GZO（MGZO）组合使用，从而形成多功能的透明复合电极。通过在玻璃基板上设计SGZO / MGZO薄膜，可以实现94.5％的高透射率和52.3 Ohm / sq的足够的薄层电阻。带有SGZO / MGZO复合阳极的经过测试的蓝色磷光OLED优于其他选择的单层电极的器件，其峰值效率高达29.0％（57.6 cd / A和47.6 lm / W）。这些结果证明了使用这种复合电极概念实现高效OLED或其他柔性光电技术的明显优势。