Post‐Passivation of Perovskite Quantum Dots by Conjugated Molecules for Spectrally Stable and Efficient Deep Blue Light‐Emitting Diodes

• DOI: 10.1002/lpor.202300390
• Publication Date: 2023-07-28T04:45:55Z
• Authors: Chenyang Shen; Yiyang Gan; Shuai Zhang; Weidong Qiu; Jiayu Li; Denghui Liu; Guanwei Sun; Zhe Liu; Guo‐Xi Yang; Xiaomei Peng; Shiping Shi; Ming‐De Li; Shi‐Jian Su
• Keywords: Passivation; Quantum Efficiency; Quantum yield

Abstract Perovskite light‐emitting diodes (PeLEDs) are promising candidates for displays and solid‐state lighting due to their tunable colors, high conversion efficiency, low cost. However, the performance of deep blue PeLEDs lags far behind that near‐infrared, red, green ones. Here, ligand concentration on perovskite surface is regulated by introducing a small organic molecule 3‐(5,9‐dioxa‐13b‐boranaphtho [3,2,1‐d,e] anthracene‐7‐yl)‐9‐phenyl‐9H‐carbazole (BOCzPh) reduce defects in mixed‐halogen lattice improve exciton binding energy quantum dots (QDs). Finally, with an emission peak at 469 nm, external efficiency 2.8%, maximum brightness 851 cd m −2 obtained. Owing post‐passivation QDs BOCzPh molecules, spectra mixed‐halide perovskites stabilized luminous devices improved simultaneously. This work provides new approach realize spectrally stable efficient PeLEDs.