Rational Interface Engineering for Efficient Flexible Perovskite Light-Emitting Diodes
Yang Shen,1 Meng-Ni Li,1 Yanqing Li,1,2,* Feng-Ming Xie,1 Hai-Yan Wu,1 Guang-Hui Zhang,1 Li Chen,1 Shuit-Tong Lee,1,3,* and Jian-Xin Tang1, 3,*
1Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou 215123, China
2School of Physics and Electronics Science, Ministry of Education Nanophotonics & Advanced Instrument Engineering Research Center, East China Normal University, Shanghai, 200062, China
3Institute of Organic Optoelectronics (IOO), JITRI, Wujiang, Suzhou 215215, China
Although perovskite light-emitting diodes (Pe-LEDs) are promising for next-generation displays and lighting, their efficiency is still considerably below that of conventional inorganic and organic counterparts. Significant efforts in various aspects of the electroluminescence process are required to achieve high-performance PeLEDs. Here, we present an improved flexible PeLED structure based on the rational interface engineering for energy-efficient photon generation and enhanced light outcoupling. The interface-stimulated crystallization and defect passivation of the perovskite emitter are synergistically realized by tuning the underlying interlayer, leading to the suppression of trap-mediated nonradiative recombination losses. Besides approaching highly emissive perovskite layers, the outcoupling of trapped light is also enhanced by combining the silver nanowires-based electrode with quasi-random nanopatterns on flexible plastic substrate. Upon the collective optimization of the device structure, a record external quantum efficiency of 24.5% is achieved for flexible PeLEDs based on green-emitting CsPbBr3 perovskite.