Zwitterions Narrow Distribution of Perovskite Quantum Wells for Blue Light‐Emitting Diodes with Efficiency Exceeding 15%

• DOI: 10.1002/adma.202208078
• Publication Date: 2022-11-18T07:54:33Z
• Authors: Shaocheng Liu; Zhenyu Guo; Xianxin Wu; Xinfeng Liu; Zijian Huang; Liang Li; Jinwen Zhang; Huanping Zhou; Ling‐Dong Sun; Chun‐Hua Yan
• Keywords: Quantum Efficiency

While quasi-two-dimensional (quasi-2D) perovskites have emerged as promising semiconductors for light-emitting diodes (LEDs), the broad-width distribution of quantum wells hinders their efficient energy transfer and electroluminescence performance in blue emission. In particular, underlying mechanism is closely related to crystallization kinetics has yet be understood. Here first time, influence bifunctional zwitterions with different coordination affinity on quasi-2D systematically investigated. The can coordinate Pb2+ also act co-spacer organic species perovskites, which collectively inhibit aggregation colloidal precursors shorten distance wells. Consequently, restricted nucleation high-n phases promoted growth low-n are achieved moderately coordinated zwitterions, leading final film a more concentrated n improved efficiency. It thus enables high-efficiency LEDs recorded external efficiency 15.6% at 490 nm, operation stability been prolonged 55.3 min. These results provide useful directions tuning expected lead high-performance perovskite LEDs.