Dual‐B‐Site Strategy Underpins Stable Unimodal Deep‐Blue Emitting Perovskites
Abstract
Abstract The operational stability of mixed‐halide blue perovskite light‐emitting diodes (PeLEDs) is fundamentally constrained by intrinsic halide ion migration. Employing single‐halide perovskite systems represents a viable route to circumvent this issue, yet solution‐processed pure‐bromide perovskites typically exhibit undesirable green emission, impeding attainment of high‐color‐purity blue electroluminescence. Herein, this challenge is addressed through the strategic incorporation of Mg 2+ into the B‐site of the pure bromine‐based perovskite lattice. This substitution induces a substantial spectral blueshift and promotes phase homogenization by facilitating efficient energy transfer from small‐n to large‐n phases. Notably, the first systematic investigation and mechanistic elucidation of the origin of bimodal emission in blue PeLEDs is presented. Consequently, the champion PeLED delivers stable deep‐blue emission at 464 nm with a maximum external quantum efficiency of 4.76%. This study presents a definitive paradigm for achieving spectrally stable and efficient deep‐blue emission from single‐halide perovskites. The elucidated mechanism underlying emission bimodality provides critical guidance for future development of blue PeLEDs.
Article Details
Authors (12)
Nan Li
Yu Xia
Xiao‐Ying He
State Key Laboratory of Bioinspired Interfacial Materials Science Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University Suzhou China
Jia‐Cheng Li
State Key Laboratory of Bioinspired Interfacial Materials Science Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University Suzhou China
Kai‐Li Wang
Institute of Functional Nano & Soft Materials (FUNSOM) State Key Laboratory of Bioinspired Interfacial Materials Science Soochow University Suzhou China
Jing Chen
Chun‐Hao Chen
Institute of Functional Nano & Soft Materials (FUNSOM) State Key Laboratory of Bioinspired Interfacial Materials Science Soochow University Suzhou China
Lei Huang
BLSA-ZJU Research Center and Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China.
Yu‐Tong Yang
Institute of Functional Nano & Soft Materials (FUNSOM) State Key Laboratory of Bioinspired Interfacial Materials Science Soochow University Suzhou China
Xin Chen
Yan‐Hui Lou
College of Energy Soochow Institute for Energy and Materials Innovations Soochow University Suzhou China
Zhao‐Kui Wang
Institute of Functional Nano & Soft Materials (FUNSOM) State Key Laboratory of Bioinspired Interfacial Materials Science Soochow University Suzhou China