Enhanced Performance of ZnO-Based Deep Red Perovskite Light-Emitting Diodes through Polyethylenimine Ethoxylated/1-
Ruoyan Wang1, Kaiming Liu1, Luman Jiang1
1Strait Institute of Flexible Electronics (SIFE, Future Technologies), Fujian Key Laboratory of Flexible Electronics and Strait Laboratory of Flexible Electronics (SLoFE), Fujian Normal University, Fuzhou, Fujian 350117, China.
Abstract:
Deep red perovskite light-emitting diodes (LEDs) based on a zinc oxide (ZnO) electron transporting layer (ETL) have achieved great improvement in recent years. Polyethylenimine ethoxylated (PEIE) is widely employed as a modification layer for ZnO in deep red perovskite LEDs to address the interfacial reaction between ZnO and perovskites. However, there is a lack of research on the regulation of the PEIE properties. In this work, we design a dual-function modification layer of PEIE doped with 1-aminopyridinium iodide (PyNI) to achieve improved energy level alignment and enhanced perovskite film quality. As a result, the deep red perovskite LEDs with a PEIE/PyNI dual-function modification layer exhibit a peak external quantum efficiency of 17.5%, a brightness of 1644 cd m-2, and extended operational stability (T50 = 8.3 h at 20 mA cm-2). These advancements highlight the critical role of ZnO surface modification in achieving high-performance ZnO-based deep red perovskite LEDs.
