Abstract:
Alternating current (AC)-driven quantum-dot light-emitting diodes (QLEDs) are superior to direct current-driven QLEDs because they can be directly integrated into household AC electricity and have high stability. However, achieving high-performance AC-driven QLEDs remains challenging. In this work, a bipolar QLED with coplanar electrodes is realized by horizontally connecting a regular QLED and an inverted QLED in series using an Al bridging layer. The bipolar QLED can be turned on with either a positive or a negative bias voltage, with a high external quantum efficiency (EQE) of 22.9%. By replacing the Al with Ag, the resistances of the electron transport layers are effectively reduced, and thus the bipolar QLED shows an enhanced brightness of 16370 cd m-2 at 15 V. By connecting multiple bipolar QLEDs in series, the resulting light source can be directly driven by a 220 V/50 Hz household power supply without the need for back-end electronics. The bipolar QLED can also be realized by vertically stacking a regular QLED and an inverted QLED with a metallic intermediate connection layer. It is demonstrated that the coplanar or vertical bipolar QLEDs could find potential applications in household AC electricity play-and-plug solid-state lighting and single- or double-sided displays.
摘要:
交流(AC)驱动的量子点发光二极管(QLED)优于直流驱动的QLED,因为它们可以直接集成到家用交流电中,并且具有很高的稳定性。然而,实现高性能AC驱动QLED仍然具有挑战性。在这项工作中,具有共面电极的双极QLED通过使用Al桥接层水平地串联连接常规QLED和倒置QLED来实现。双极QLED可以通过正偏置电压或负偏置电压打开,具有22.9%的高外部量子效率(EQE)。用Ag代替Al,有效地降低了电子传输层的电阻,因此,双极QLED在15V时显示出16370cd/m2的增强亮度。通过串联连接多个双极QLED,所得到的光源可以直接由220V/50Hz的家用电源驱动,而不需要后端电子设备。双极QLED也可以通过垂直堆叠规则QLED和具有金属中间连接层的反向QLED来实现。我们证明,共面或垂直双极QLED可以在家用交流电播放和插头固态照明以及单面或双面显示器中找到潜在的应用。本文受版权保护。保留所有权利。