High‐Performance NIR‐II Sn‐Based Perovskite LEDs Enabled by the Functionalization of Sulfaguanidine
Abstract
ABSTRACT Eco‐friendly CsSnI 3 ‐based perovskite light‐emitting diodes (PeLEDs) with the emission peak extending to the near‐infrared‐II (NIR‐II) region hold tremendous potential for applications in biological monitoring, night vision, and optical communications. However, the various defects caused by the instability of Sn 2+ within the CsSnI 3 film, and the non‐equilibrium carrier injection rate in the devices are the two major factors that limit the device performance. Here, we report high‐performance NIR‐II CsSnI 3 ‐based PeLEDs achieved by employing functional sulfaguanidine (SG) molecules. Due to the strong S═O─Sn coordination bonds, NH 2 ···I − hydrogen bonds could be formed between CsSnI 3 and SG, which effectively eliminated various Sn(II)‐related defects in the CsSnI 3 film. Moreover, the SG molecules significantly improved the morphological uniformity and regulated the carrier injection balance, resulting in more balanced carrier injection that enhanced the effective radiation recombination rate. Consequently, the optimized CsSnI 3 ‐SG PeLEDs achieved a breakthrough external quantum efficiency (EQE) of 8.1%, which is the highest efficiency reported for CsSnI 3 ‐based PeLEDs to date.
Article Details
Authors (21)
Xiuling Li
Yuechuan Bi
Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Chengdu P. R. China
Xiang Guan
Jiaqi Wang
Jinli Liu
Yingjie Zhao
College of Chemistry and Pingyuan Laboratory
Chunli Zhao
Zhuojian Li
Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Chengdu P. R. China
Shurui Chi
Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Chengdu P. R. China
Junnan Wang
Renjing Chen
Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Chengdu P. R. China
Zixun Zhao
Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Chengdu P. R. China
Zemin Wang
Xin Tong
Ninggui Ma
Department of Materials Science and Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong 999077, China
Han Liu
Department of Chemistry, State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong SAR 999077, P. R. China
Zhiming Wang
State Key Laboratory of Luminescent Materials and Devices, and Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates
Zongwen Liu
School of Chemical and Biomolecular Engineering, The University of Sydney 3 , Sydney, New South Wales 2006,
Yang Ren
Zhanhua Wei
Kebin Lin