Organic light-emitting diodes (OLEDs) with thick carrier transport layers are desirable for high production yields of OLED-based displays and lighting; however, high operating voltages are inevitably introduced to thick OLEDs due to the low carrier mobilities of organics. The associated Joule heating will also induce structural defects and lower operational stabilities. Here we demonstrate highly efficient and stable OLEDs with thicknesses of over 1 μm and low operating voltages. The OLEDs use MoO₃/SimCP2 as a hole-injection layer and a thick layer of 4,4′-(cyclohexane-1,1-diyl)bis(N,N-di-p-tolylaniline) (TAPC) as a hole-transporting layer. We find that Ohmic hole injection can only be formed for TAPC layers with thicknesses of over 900 nm. In this configuration, we achieve external quantum efficiencies of 23.09%, 22.19% and 7.39%, and operating voltages of 5.11 V, 3.55 V and 6.88 V at 1,000 cd cm^–2 for red, green and blue OLEDs, respectively. We also incorporate a thin layer of HAT-CN between the TAPC and electron-blocking layers to suppress electron leakage. The red, green and blue OLEDs in this work maintained the above-mentioned performances while also featuring excellent extrapolated LT₉₅ operational lifetimes of around 55,000 h, 18,000 h and 1,600 h, respectively, at an initial luminance of 1,000 cd cm^–2. We believe that our work paves the way for large-area OLED-based displays and lighting with high production yields.

具有厚载流子传输层的有机发光二极管 (OLED) 对于基于 OLED 的显示器和照明的高产量是理想的；然而，由于有机物的低载流子迁移率，高工作电压不可避免地被引入厚 OLED。相关的焦耳加热也将导致结构缺陷和较低的操作稳定性。在这里，我们展示了厚度超过 1 μm 和低工作电压的高效且稳定的 OLED。OLED 使用 MoO ₃ /SimCP2 作为空穴注入层和厚的 4,4'-(cyclohex-1,1-diyl)bis( N , N -di- p-tolylaniline) (TAPC) 作为空穴传输层。我们发现欧姆空穴注入只能用于厚度超过 900 nm 的 TAPC 层。在这种配置中，我们实现了 23.09%、22.19% 和 7.39% 的外部量子效率，红色、绿色和蓝色 OLED在 1,000 cd cm ^–2下的工作电压分别为 5.11 V、3.55 V 和 6.88 V。我们还在 TAPC 和电子阻挡层之间加入了一层薄薄的 HAT-CN，以抑制电子泄漏。这项工作中的红色、绿色和蓝色 OLED 保持了上述性能，同时还具有出色的外推 LT ₉₅工作寿命，分别约为 55,000 小时、18,000 小时和 1,600 小时，初始亮度为 1,000 cd cm ^{- 2}. 我们相信，我们的工作为高产量的大面积 OLED 显示器和照明铺平了道路。