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Quantum dot light-emitting diodes (QD-LEDs) have approached the theoretical limit of external quantum efficiency (EQE) determined by outcoupling efficiency. To achieve further improvements, novel optical designs must be explored, such as constructing optical microcavities, utilizing light scattering, or tuning the orientation of transition dipole moments (TDM). This study reports advances in red rod-in-rod quantum rods (QRs) film that exhibits a high in-plane dipole orientation of 82%, achieved through shape-induced horizontal self-alignment. Also a critical issue is discovered: the carrier leakage through irregular quantum rod films, which hinders the EQE of quantum rod light-emitting diodes (QR-LEDs) and limits its competitiveness with QD-LEDs. An equivalent circuit model comprising two diodes clearly illustrates the impacts of the leakage current within conventional QR-LED structures. By transforming the QR-LEDs device structure, balanced carrier injection and suppressed leakage current are simultaneously enhanced, achieving a red QR-LEDs with a peak EQE of 31% and a peak brightness of 110 000 cd m . Additionally, these strategies are applied to green dot-in-rod QRs, demonstrating a peak EQE of 20.2% with ultra-high luminance of 250 000 cd m . This work is expected to pave the way for further improvements in the LED performance based on anisotropic nanocrystals.
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http://dx.doi.org/10.1002/adma.202504559 | DOI Listing |
J Am Chem Soc
September 2025
Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710127, China.
The ordered growth of semiconductor quantum dots (QDs) in confined environments remains a critical challenge in photocatalysis. Herein, CsBiBr (CBB) QDs were covalently anchored as single-rod nanocrystals (SRNCs) within Hf-based metal-organic framework (MOF) nanosheets (Hf-bpy, Hbpy = 2,2'-bipyridine-5,5'-dicarboxylic acid), forming a series of host-guest photocatalysts CBB@Hf-bpy. By modulation of the thickness of MOF nanosheets, the length of CBB SRNCs was effectively shortened to 18 nm, exhibiting strong quantum confinement effects.
View Article and Find Full Text PDFAdv Mater
August 2025
State Key Laboratory of Displays and Optoelectronics, Department of Electronics and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, 999077, P. R. China.
Quantum dot light-emitting diodes (QD-LEDs) have approached the theoretical limit of external quantum efficiency (EQE) determined by outcoupling efficiency. To achieve further improvements, novel optical designs must be explored, such as constructing optical microcavities, utilizing light scattering, or tuning the orientation of transition dipole moments (TDM). This study reports advances in red rod-in-rod quantum rods (QRs) film that exhibits a high in-plane dipole orientation of 82%, achieved through shape-induced horizontal self-alignment.
View Article and Find Full Text PDFACS Appl Mater Interfaces
August 2025
Department of Materials Science and Engineering, School of Materials and Chemical Technology, Institute of Science Tokyo, Tokyo 152-8552, Japan.
Although visible-light-responsive SnO is known to be synthesized by a hydrothermal method, its reported crystal structure is limited to the monoclinic phase. Recently, orthorhombic SnO has been reported as a new polymorph of tin oxides; however, its photocatalytic properties have not been examined. This paper reports the thin film synthesis of orthorhombic SnO and its photocatalytic properties under visible-light irradiation.
View Article and Find Full Text PDFThe use of the stack-and-draw method to fabricate photonic crystal fibers (PCFs) depends on the precise optimization of filler rod parameters, such as the size, positional accuracy, and tolerance. Traditional manual design methods employing tools such as AutoCAD rely on manual effort and experience, often resulting in inconsistencies and limited precision. In this study, we propose an automated design framework based on an improved genetic algorithm (IGA) incorporating what we beleive to be a novel antagonism balance criterion, which systematically addresses these limitations by autonomously determining the optimal parameters of the filler rods.
View Article and Find Full Text PDFJ Am Chem Soc
August 2025
Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States.
Converting near-infrared (NIR) photons into visible light via triplet-triplet annihilation upconversion (TTA-UC) is a promising strategy for advancing energy, biomedical, and materials science. However, the development of efficient NIR sensitizers remains a major challenge. Here, we report an atomically precise gold quantum rod, Au(PET) (PET = 2-phenylethanethiolate), as a high-performance photosensitizer for NIR-to-visible TTA-UC.
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