posted on 2024-03-04, 14:03authored byYuting Xu, Xingxing Tan, Lanlan Zhai, Yingyu Wang, He Huang, Guanghong Yang, Dicai Zhuang, Yun Yang, Lijie Zhang, Chao Zou
Incorporating a chlorine ion into a bromine-based perovskite
is
a straightforward strategy to achieve blue perovskite light-emitting
diodes (PeLEDs). However, efficient deep-blue PeLEDs suffer from ineffective
chlorine ion supplementation due to the low solubility of chloride
and high deep-level defects in perovskite. Here, we propose multifunctional
zwitterion choline chloride (ChCl) and rubidium bromide (RbBr) molecules,
which not only provide free chlorine ion to fill the halide vacancies
but also serve as passivating agents to eliminate Pb0 defects
in perovskite nanosheets. Consequently, deep-blue PeLEDs were achieved
with peak external quantum efficiencies of 3.58%, 2.41%, and 1.10%,
which coordinate at (0.134, 0.063), (0.139, 0.052), and (0.141, 0.041),
respectively.