In Situ Interface Reaction Enables Efficient Deep‐Blue Perovskite Light‐Emitting Diodes
Abstract
Abstract The development of blue perovskite light‐emitting diodes (PeLEDs) is critical for advancing next‐generation display technologies. However, the fabrication of high‐quality mixed‐halide blue perovskites remains challenging due to their intrinsic vulnerability to high defect densities, ion migration, and inefficient charge transport. To address this, we introduce a rapid in situ interface reaction at the buried interface between the perovskite layer and the underlying poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) film. This engineered interface reaction represents a novel method for preparing high‐quality deep‐blue CsPb(Br/Cl) 3 films. By incorporating lithium salicylate (SAL) as a reaction initiator into the perovskite precursor, a proton exchange is triggered between PEDOT:PSS and SAL, resulting in the formation of a multifunctional PSS‐Li interfacial layer. This layer modulates perovskite nucleation and growth, producing compact, uniform, and small‐grained deep‐blue perovskite films with reduced trap densities and enhanced quantum confinement. Combined with optimized charge dynamics, the resulting spectrally stable deep‐blue PeLEDs achieve a record external quantum efficiency of 16.3% at 468 nm. This approach facilitates the successful integration of uniform and high‐clarity active‐matrix displays on thin‐film transistor circuit substrates.
Article Details
Authors (15)
Long‐Xue Cao
Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon‐Based Functional Materials & Devices Soochow University Suzhou 215123 China
Yang Shen
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics
Kai Zhang
Zhen‐Huang Su
Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory Chinese Academy of Sciences Shanghai 200241 China
Shi‐Chi Feng
Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon‐Based Functional Materials & Devices Soochow University Suzhou 215123 China
Xin‐Mei Hu
Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon‐Based Functional Materials & Devices Soochow University Suzhou 215123 China
Yu‐Hang Zhang
State Key Laboratory For Physical Chemistry of Solid Surfaces Innovation Laboratory for Sciences and Technologies of Energy Material of Fujian Province (IKKEM) Collaborative Innovation Center of Chemistry for Energy Materials (<i>i</i>ChEM) Engineering Research Center of Electrochemical Technologies of Ministry of Education, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University Xiamen Fujian China
Bing‐Feng Wang
School of Physics and Electronic Science East China Normal University Shanghai 200062 China
Ying‐Ying Li
Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University Suzhou Jiangsu China
Xingyu Gao
Wen‐Jun Wang
State Key Laboratory of Chemical Engineering College of Chemical and Biological Engineering Zhejiang University Hangzhou Zhejiang P. R. China
Satoshi Kera
Institute for Molecular Science National Institutes of Natural Sciences, Myodaiji Okazaki 444‐8585 Japan
Nobuo Ueno
Graduate School of Advanced Integration Science Chiba University Chiba 263‐8522 Japan
Yan‐Qing Li
School of Physics East China Normal University Shanghai P. R. China
Jian‐Xin Tang
Jiangsu Key Laboratory For Carbon‐Based Functional Materials & Devices Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University Suzhou Jiangsu P. R. China