Affiliation:
1. Key Laboratory of Polar Materials and Devices (MOE) Department of Electronics East China Normal University Shanghai 200241 P. R. China
2. Collaborative Innovation Center of Extreme Optics Shanxi University Taiyuan Shanxi 030006 P. R. China
3. Key Laboratory of Functional Metal‐Organic Compounds of Hunan Province Hengyang Normal University Hengyang Hunan 421008 P. R. China
4. School of Physical Science and Technology ShanghaiTech University Shanghai 201210 P. R. China
Abstract
AbstractAlthough tremendous advances have recently been achieved in perovskite light‐emitting diodes (PeLEDs), development of the blue PeLEDs needed to achieve full‐color displays is far behind the red and green counterparts. Here, a simple and effective interface engineering strategy is reported to achieve efficient blue PeLEDs by modifying poly(3, 4‐ethylene dioxythiophene):polystyrene sulfonic (PEDOT:PSS) substrate with an amphiprotic molecule glycine. As a multifunctional additive, glycine can not only modulate the pH of PEDOT:PSS, but also trigger strong interfacial effect. Cooperative coordination and hydrogen bonding interactions between glycine and perovskite at the interface can passivate the interfacial defects and manipulate upper perovskite crystallization. Therefore, high‐quality perovskite films with grade‐distributed phases are obtained, enabling efficient cascade energy transfer and suppression of leakage current. The resulting PeLED exhibits the electroluminescence (EL) peak at 473 nm with a maximum external quantum efficiency (EQE) of 7.2%, which is ≈5.5 times that of the unmodified device. Realizing the regulation of low‐dimensional phase distribution of quasi‐2D perovskites through interfacial effect provides a reliable way to fabricate efficient blue PeLEDs.
Funder
National Key Research and Development Program of China
National Natural Science Foundation of China
Subject
Atomic and Molecular Physics, and Optics,Electronic, Optical and Magnetic Materials