Crystallographic Engineering to Develop Ultra‐Narrow‐Band Cyan‐Emitting UCr₄C₄‐Type Phosphor for Healthy LED Lighting and Display

Laser & Photonics Review, Journal Year: 2024, Volume and Issue: 18(11)

Published: June 18, 2024

Abstract Narrow‐band cyan‐emitting materials for white light‐emitting diode (wLED) application have shown great potential in increasing the maximum accessible display gamut and improving color rendering of full‐spectrum healthy lighting. However, discovery novel narrow‐band cyan emitters with excellent luminescence performances remains challenging. Here, an ultra‐narrow‐band Na 5 K 3 (Li SiO 4 ) 8 :Eu 2+ (N phosphor (λ em = 483 nm) full width at half (FWHM) only 18 nm is developed from some typical UCr C frameworks phosphors by slightly modifying crystal structure symmetry. Through controllable regulation ratio 6 2 to N , lattice sites forming shoulder peaks are further squeezed generate narrowest emission. Moreover, exhibits low photoluminescence thermal quenching (90%@150 °C) high internal quantum efficiency (IQE) 50%. The index wLED health lighting enhanced 92 94. Using this short‐wavelength emission instead a part blue chip can effectively prevent “blue hazard”. This work provides basic principles design phosphors, thus achieving their applications fields eye‐friendly display.

Language: Английский

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Temperature-dependent self-trapped models regulating energy transfer in rare earth double perovskites via 5s² electron doping

Inorganic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(12), P. 3607 - 3617

Published: Jan. 1, 2024

Sb 3+ /Sm co-doping can effectively modulate the luminescence by adjusting energy transfer in Cs 2 NaYCl 6 double perovskites. Two minima excited state of 3 P 1 enable self-trapped exciton emission at low temperatures.

Language: Английский

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Synthesis of Metastable Silver-Lanthanide Double Perovskite Nanocrystals with White-Light Emission

Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 63(4), P. 2241 - 2246

Published: Jan. 12, 2024

Four silver-lanthanide double perovskite nanocrystals, namely, Cs2AgSmCl6, Cs2AgEuCl6, Cs2AgGdCl6, and Cs2AgErCl6, were synthesized for the first time. These four perovskites have yet to be reported in any form are found metastable bulk phase. By using colloidal hot-injection synthesis method, phase can arrested kinetically. lead-free nanocrystals show a broadband emission owing self-trapped exciton recombination, with Cs2AgEuCl6 exhibiting characteristic f–f from Eu3+.

Language: Английский

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Pressure-Induced Structural Phase Transitions and Photoluminescence Properties of Micro/Nanocrystals HoF₃

Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 63(43), P. 20562 - 20571

Published: Oct. 15, 2024

HoF

Language: Английский

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Near‐Complete Suppression of NIR‐II Luminescence Quenching in Halide Double Perovskites for Surface Functionalization Through Facet Engineering

Advanced Science, Journal Year: 2024, Volume and Issue: 11(32)

Published: June 26, 2024

Abstract Lanthanide‐based NIR‐II‐emitting materials (1000–1700 nm) show promise for optoelectronic devices, phototherapy, and bioimaging. However, one major bottleneck to prevent their widespread use lies in low quantum efficiencies, which are significantly constrained by various quenching effects. Here, a highly oriented (222) facet is achieved via engineering Cs 2 NaErCl 6 double perovskites, enabling near‐complete suppression of NIR‐II luminescence quenching. The optimally (222)‐oriented Ag 0.10 Na 0.90 ErCl microcrystals emit Er 3+ 1540 nm light with unprecedented high efficiencies 90 ± 6% under 379 UV excitation (ultralarge Stokes shift >1000 nm), record near‐unity yield 98.6% also obtained (222)‐based NaYb 0.40 0.60 Cl microcrystallites 980 excitation. With combined experimental theoretical studies, the underlying mechanism facet‐dependent emissions revealed, can contribute surface asymmetry‐induced breakdown parity‐forbidden transition undesired non‐radiative processes. Further, role reexamined molecular dynamics based on two facets, highlighting drastic two‐phonon coupling effect hydroxyl group 4 I 13/2 level . Surface‐functionalized facets will provide new insights tunable open up avenue developing efficient emitters toward broad applications.

Language: Английский

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Cation‐Doped Cs₂B^IB^IIIX₆ Double Perovskites: Electronic Structures, Optical Properties, and Optoelectronic Applications

Advanced Optical Materials, Journal Year: 2024, Volume and Issue: 12(30)

Published: Aug. 13, 2024

Abstract Recently, all‐inorganic halide double perovskites (DPs) with a chemical formula of Cs 2 B I III X 6 have been emerging as shinning star to be used in modern optoelectronic devices, due their unique advantages such environmentally friendly, high absorption coefficient, low trap densities, tunable bandgap, variable constituent elements and valences states through or sites engineering. In this review, first, the impact cation doping on electronic structure optical properties DPs are systematically overviewed, which cover several key issues including interconversion between direct indirect band gaps, enhancement light absorption, promotion exciton localization, elucidation energy transfer mechanisms, regulation defect density improvement both stability luminescence efficiency. Subsequently, state‐of‐the‐art research activities regarding interesting device applications discussed, light‐emitting diodes, anticounterfeiting encryption, X‐ray scintillators, thermometry. Finally, existing difficulties, prospects, directions field proposed.

Language: Английский

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Activate Reconstruction from Sb³⁺/Ho³⁺ Synergistic Doping Nanofibers for Interactive Information Encryption and Customized Display

Laser & Photonics Review, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 12, 2025

Abstract Driven by the escalating demand for cutting‐edge materials in interactive encryption and customized display, optimization of excitonic coupling mechanisms perovskite‐based luminescent systems has emerged as a pivotal focus advanced research. Inspired synergistic doping (SD), photoswitchable energy transfer channel is realized utilizing UV‐responsive Cs 2 NaInCl 6 : Sb 3+ ‐Ho (CNIC: Sb‐Ho) phosphor. Benefiting from self‐trapped exciton , visible blue luminescence Ho achieves excitation reconstruction through SD, with sensitization coefficient to CNIC reaching two orders magnitude. Notably, CNIC: Sb‐Ho quantum dot embedded into polyacrylonitrile (PAN) polymethyl methacrylate (PMMA) fibers, respectively, distinct color coordinate channels are created altering concentration fiber matrix, thereby enabling personalization customization desired colors enhanced precision. Furthermore, excellent read‐in performance under UV irradiation achieved screen‐printing microcrystal on nanofibers combining it ACSII code, which endows UV‐induced controllable shape programming behavior multidimensional information encryption. This work establishes an visual interaction framework effectively integrating perovskite fluorescence tunability nanofiber adaptive structures, thus opening new possibilities smart application next‐generation optical technology.

Language: Английский

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Photochromic −Activity Relationship Insights for Boosting C(Sp3)-H Bonds Activation in the Biobr1-Xix Colloid Ultrathin Nanosheets

Published: Jan. 1, 2025

Language: Английский

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Novel Lead‐Free Stable Fluorite Nanocrystals and Their Applications in Light‐Emitting Diodes

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: May 2, 2025

Abstract The toxicity and the poor thermal stability of all‐inorganic lead perovskite nanocrystals (NCs) have been major limitation for their scale‐up purpose. In this study, a novel lead‐free KEu 4 F 13 NCs are synthesized first time using facile eco‐friendly hydrothermal strategy. High‐resolution synchrotron X‐ray diffraction study indicates that adopt cubic fluorite structure with excess fluorine intercalated into spare rooms lattice. obtained characteristic emission peaks Eu 3+ ions excited by wavelength 394 nm. More importantly, show excellent due to small radius − its high lattice energy. relative photoluminescence (PL) intensity at 594 nm retains ≈72% initial value 20 °C when heated 200 °C. Furthermore, PL shows negligible degradation after undergoing three consecutive cycles between (XRD) remain identical those cycled samples (after 1st/3rd cycles), confirming structural robustness under stress. lifetimes measured 180 calculated be 2.10 2.04 ms, respectively. red‐emitting encapsulated on an ultraviolet (UV)‐emitting chip fabricate red light‐emitting diodes (LED).

Language: Английский

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Symmetry Disruption and Charge Localization: Unraveling Roles of Sb³⁺ in Enhancing Luminescence of Rare Earth Double Perovskites

Laser & Photonics Review, Journal Year: 2025, Volume and Issue: unknown

Published: April 25, 2025

Abstract Co‐doping of rare earth (RE) and ns 2 metal ions with in double perovskites shows great promise for applications anti‐counterfeiting, display, radiation detection. However, the intrinsic physical nature enhanced photoluminescence remains unclear. Herein, we use gadolinium‐based perovskite as model propose an effective strategy co‐doping RE3+ Sb3+ (5s ) to modulate energy transfer. The incorporation Sb 3+ increases absorption cross section, thereby overcoming limitation 4f–4f narrowband transitions. Furthermore, acts a bridge transfer, significantly facilitating this process. Density functional theory calculations reveal that introduction disrupts symmetry [RECl 6 ] 3– octahedra, leading increased distortion. Additionally, electrons octahedra exhibit stronger localization /RE co‐doped system, which enhances Cl – –RE charge transfer process, increasing radiative transition rates resulting high quantum yield. Our research elucidates essence luminescence RE‐based from both experimental theoretical perspectives, providing valuable insights into modulation luminescent properties understanding underlying mechanisms RE doped materials.

Language: Английский

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