i-Lab , Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Science , Suzhou , Jiangsu 215123 , China.
Joint International Research Laboratory of Information Display and Visualization, School of Electronic Science and Engineering , Southeast University , Nanjing , Jiangsu 210096 , China.
ACS Appl Mater Interfaces. 2018 Apr 18;10(15):13236-13243. doi: 10.1021/acsami.8b01684. Epub 2018 Apr 6.
All-inorganic perovskite light-emitting diode (PeLED) has a high stability in ambient atmosphere, but it is a big challenge to achieve high performance of the device. Basically, device design, control of energy-level alignment, and reducing the energy barrier between adjacent layers in the architecture of PeLED are important factors to achieve high efficiency. In this study, we report a CsPbBr-based PeLED with an inverted architecture using lithium-doped TiO nanoparticles as the electron transport layer (ETL). The optimal lithium doping balances the charge carrier injection between the hole transport layer and ETL, leading to superior device performance. The device exhibits a current efficiency of 3 cd A, a luminance efficiency of 2210 cd m, and a low turn-on voltage of 2.3 V. The turn-on voltage is one of the lowest values among reported CsPbBr-based PeLEDs. A 7-fold increase in device efficiencies has been obtained for lithium-doped TiO compared to that for undoped TiO-based devices.
全无机钙钛矿发光二极管（PeLED）在环境气氛中具有高稳定性，但要实现器件的高性能仍是一个巨大的挑战。基本上，器件设计、能级对准的控制以及减少 PeLED 结构中相邻层之间的能量势垒是实现高效率的重要因素。在这项研究中，我们报告了一种基于 CsPbBr 的 PeLED，采用掺锂 TiO 纳米粒子作为电子传输层（ETL）的倒置结构。最佳的锂掺杂平衡了空穴传输层和 ETL 之间的电荷载流子注入，从而获得了优异的器件性能。该器件的电流效率为 3 cd A，亮度效率为 2210 cd m，开启电压低至 2.3 V。开启电压是已报道的基于 CsPbBr 的 PeLED 中最低的值之一。与未掺杂 TiO 基器件相比，掺锂 TiO 基器件的器件效率提高了 7 倍。
