The poor efficiency and stability of blue Quantum Dot Light-Emitting diodes (QLED) hinders the practical applications of QLEDs full-color displays. Excessive electron injection, insufficient hole injection, and abundant defects on the surface of quantum dots (QD) are the main issues limiting the performance of blue devices. Herein, an in situ treatment with bipolar small molecule polydentate ligand-guanidine chloride (GACl) is proposed to simultaneously suppress excessive electron injection, patch surface defects of QDs and enhance hole injection. GACl-treated blue QLEDs exhibited a remarkable increase in maximal external quantum Efficiency (EQE) from 16.3% to a record 23.5%, accompanied by maximal luminance (36810 cd m), excellent maximal current efficiency (17.5 cd A), and enhanced device stability. Combining C-V and J-V characteristics, a concise physical model of hole injection is also established: Below 3 V, hole injection is controlled by the interfacial barrier, primarily through tunneling and thermionic injection; Above 3 V, the interfacial barrier is eliminated, and hole injection efficiency is governed by transport within the QD layer. This study showed a clear physical model for understanding the hole injection mechanism in QLEDs, offering valuable design strategies for improving the performance of blue-QLEDs.
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http://dx.doi.org/10.1002/adma.202413183 | DOI Listing |
Adv Mater
January 2025
National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Key Lab for Special Functional Materials of Ministry of Education, School of Nanoscience and Materials Engineering, Henan University, Kaifeng, 475004, China.
The poor efficiency and stability of blue Quantum Dot Light-Emitting diodes (QLED) hinders the practical applications of QLEDs full-color displays. Excessive electron injection, insufficient hole injection, and abundant defects on the surface of quantum dots (QD) are the main issues limiting the performance of blue devices. Herein, an in situ treatment with bipolar small molecule polydentate ligand-guanidine chloride (GACl) is proposed to simultaneously suppress excessive electron injection, patch surface defects of QDs and enhance hole injection.
View Article and Find Full Text PDFNat Commun
January 2025
Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping, Sweden.
One of the key advantages of perovskite light-emitting diodes (PeLEDs) is their potential to achieve high performance at much higher current densities compared to conventional solution-processed emitters. However, state-of-the-art PeLEDs have not yet reached this potential, often suffering from severe current-efficiency roll-off under intensive electrical excitations. Here, we demonstrate bright PeLEDs, with a peak radiance of 2409 W sr m and negligible current-efficiency roll-off, maintaining high external quantum efficiency over 20% even at current densities as high as 2270 mA cm.
View Article and Find Full Text PDFCarbohydr Polym
March 2025
College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China; School of Chemistry, Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, South China Normal University, Guangzhou 510006, China. Electronic address:
The management of wounds infected with drug-resistant bacteria represents a significant challenge to public health globally. Nanotechnology-functionalized photothermal hydrogel with good thermal stability, biocompatibility and tissue adhesion exhibits great potential in treating these infected wounds. Herein, a novel photothermal hydrogel (mCS-Cu-Ser) was prepared through in situ mineralization in the hydrogel networks and ion cross-linking driven by copper ions (∼3 mM).
View Article and Find Full Text PDFRetin Cases Brief Rep
January 2025
Herbert Wertheim College of Medicine, Florida International University, Miami, Florida, USA.
Purpose: To report a case of drusen regression following pars plana vitrectomy with internal limiting membrane peel (ILMP) in a patient with a full-thickness macular hole and dry age-related macular degeneration (AMD).
Methods: A 67-year-old gentleman presented in April 2024 with a full-thickness macular hole in OS and intermediate dry AMD OU. The patient underwent pars plana vitrectomy, ILMP, and an injection of sulfur hexafluoride gas for macular hole repair in OS.
Light Sci Appl
January 2025
Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, Henan University, 475004, Kaifeng, China.
Solution-processed quantum dot light-emitting diodes (QLEDs) hold great potential as competitive candidates for display and lighting applications. However, the serious energy disorder between the quantum dots (QDs) and hole transport layer (HTL) makes it challenging to achieve high-performance devices at lower voltage ranges. Here, we introduce "giant" fully alloy CdZnSe/ZnSeS core/shell QDs (size ~ 19 nm) as the emitting layer to build high-efficient and stable QLEDs.
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