Highly ordered inkjet-printed quantum-dot thin films enable efficient and stable QLEDs with EQE exceeding 23%
Changting Wei,
Bo Xu,
Meng Zhang,
Zhenhuang Su,
Jiawei Gu,
Wenrui Guo,
Xingyu Gao,
Wenming Su,
Zheng Cui,
Seokwoo Jeon,
Zhiyong Fan,
Haibo Zeng
Affiliations
Changting Wei
MIIT Key Laboratory of Advanced Display Materials and Devices, Institute of Optoelectronics & Nanomaterials, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
Bo Xu
MIIT Key Laboratory of Advanced Display Materials and Devices, Institute of Optoelectronics & Nanomaterials, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; Corresponding authors.
Meng Zhang
Ningbo Nato New Material Technology Co., Ltd, Ningbo 315600, China
Zhenhuang Su
Shanghai Synchrotron Radiation Facility (SSRF), Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
Jiawei Gu
School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, China
Wenrui Guo
Printable Electronics Research Center, Nano Devices and Materials Division, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
Xingyu Gao
Shanghai Synchrotron Radiation Facility (SSRF), Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
Wenming Su
Printable Electronics Research Center, Nano Devices and Materials Division, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China; Corresponding authors.
Zheng Cui
Printable Electronics Research Center, Nano Devices and Materials Division, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
Seokwoo Jeon
Department of Materials Science and Engineering, Korea University, Seoul 02841, South Korea
Zhiyong Fan
Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Hong Kong 999077, China
Haibo Zeng
MIIT Key Laboratory of Advanced Display Materials and Devices, Institute of Optoelectronics & Nanomaterials, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; Corresponding authors.
Inkjet-printed quantum dot light-emitting diodes (QLEDs) are emerging as a promising technology for next-generation displays. However, the progress in fabricating QLEDs using inkjet printing technique has been slower compared to spin-coated devices, particularly in terms of efficiency and stability. The key to achieving high performance QLEDs lies in creating a highly ordered and uniform inkjet-printed quantum dot (QD) thin film. In this study, we present a highly effective strategy to significantly improve the quality of inkjet-printed CdZnSe/CdZnS/ZnS QD thin films through a pressure-assisted thermal annealing (PTA) approach. Benefiting from this PTA process, a high quality QD thin film with ordered packing, low surface roughness, high photoluminescence and excellent electrical property is obtained. The mechanism behind the PTA process and its profound impact on device performance have been thoroughly investigated and understood. Consequently, a record high external quantum efficiency (EQE) of 23.08% with an impressive operational lifetime (T50) of up to 343,342 h@100 cd m−2, and a record EQE of 22.43% with T50 exceeding to 1,500,463 h@100 cd m−2 are achieved in inkjet-printed red and green CdZnSe-based QLEDs, respectively. This work highlights the PTA process as an important approach to realize highly efficient and stable inkjet-printed QLEDs, thus advancing QLED technology to practical applications.
