A5057081941- Luminescence Properties of Advanced Materials
- Quantum Dots Synthesis And Properties
- Perovskite Materials and Applications
- Luminescence and Fluorescent Materials
- Advanced Photocatalysis Techniques
- Chalcogenide Semiconductor Thin Films
- Gas Sensing Nanomaterials and Sensors
- Radiation Detection and Scintillator Technologies
- ZnO doping and properties
- Organic Light-Emitting Diodes Research
- Transition Metal Oxide Nanomaterials
- Nanocluster Synthesis and Applications
- Inorganic Fluorides and Related Compounds
- Nanoplatforms for cancer theranostics
- Conducting polymers and applications
- Ga2O3 and related materials
- Advanced biosensing and bioanalysis techniques
- Glass properties and applications
- Photochemistry and Electron Transfer Studies
- Solid State Laser Technologies
- Photonic Crystals and Applications
- bioluminescence and chemiluminescence research
- GaN-based semiconductor devices and materials
- Copper-based nanomaterials and applications
- Inorganic Chemistry and Materials
Korea Institute of Science and Technology
2016-2025
Korea University of Science and Technology
2016-2025
Korea Institute of Oriental Medicine
2025
Seoul Institute
2018-2019
Government of the Republic of Korea
2017-2019
Korea Advanced Institute of Science and Technology
2006-2012
Daegu Gyeongbuk Institute of Science and Technology
2011
Purdue University West Lafayette
2009-2010
Seoul National University
2006
Locus Pharmacy (United States)
2006
White LEDs are fabricated through a combination of blue with Sr3SiO5:Ce3+,Li+ phosphors and organically capped CdSe quantum dots (QDs), which exhibit 2D superlattice. The emission from the LEDs, greenish-yellow phosphors, red QDs generates white light. As-synthesized show excellent color rendering properties stable coordinates against increasing forward bias currents (see figure). Supporting information for this article is available on WWW under...
Highly efficient phosphor materials with superior thermal stability are indispensable for phosphor-converted white light-emitting diodes (pc-WLEDs) solid state lighting. In order to obtain a high quality warm light, near-ultraviolet (n-UV) chips combined trichromatic phosphors have be extensively studied. Among them, the development of blue remains challenging task. view close correlation between 5d–4f transitions rare earth ions and coordination environment host lattice, many studies been...
Here, excitation orthogonalized red/green/blue upconversion luminescence (UCL)-based full-color tunable rare-earth (RE) ion-doped nanophosphors (UCNPs) are reported. The LiREF4-based core/sextuple-shell (C/6S) UCNPs synthesized, and they consist of a blue-emitting core, green-emitting inner shell, red-emitting outer with inert intermediate outermost shells. synthesized C/6S emit blue, green, red light under 980, 800, 1532 nm, respectively. Importantly, by combining incident near-infrared...
In this letter, a yellow-emitting Sr3SiO5:Ce3+,Li+ phosphor is reported. Through transitions of 5d→4f (F7∕22 and F5∕22) in Ce3+, the showed very broad strong yellow emission under near ultraviolet (UV) or blue light excitation. The energy levels Ce3+ Sr3SiO5 were suggested from its absorption excitation spectra. White could be obtained by combining with 460 405nm light-emitting diodes (LEDs) [(x,y)=(0.3086,0.3167) (0.3173, 0.3103)]. Additionally, LED was fabricated using near-UV (380nm chip)...
On the basis of structural information that host material has excellent charge stabilization, blue-emitting Ca(6-x-y)Mg(x)(PO(4))(4):Eu(y)(2+) (CMP:Eu(2+)) phosphors were synthesized and systematically optimized, their photoluminescence (PL) properties evaluated. Depending upon amount Mg added, emission efficiency could be enhanced. The substitution Eu(2+) affected maximum wavelength (lambda(max)) thermal stability because site varied. To obtain single-phase two-color-emitting phosphors, we...
Abstract Lead halide perovskite quantum dots (PQDs) have been widely recognized as highly luminescent materials for efficient optoelectronic applications owing to their fascinating electronic and optical properties. In spite of the excellent performances fabrication lighting devices, poor chemical instability greatly hampers practical applications. The inevitable ion exchange degradation driven from light, moisture, heat, others limits such solid‐state light‐emitting diodes (LEDs). this...
In this study, we report bright yellow-green-emitting CuInS2 (CIS)-based quantum dots (QDs) and two-band white light-emitting diodes (LEDs) using them. To achieve high efficiency (QE) of CIS QDs, core/shell/shell strategy was introduced to quality cores (QE = 31.7%) synthesized by metal–oleate precursors 1-dodecanethiol. The CIS/ZnS/ZnS QDs showed a QE 80.0% peak wavelength 559 nm under the excitation 450 nm, which is well matched with dominant blue LEDs. formation structure confirmed X-ray...
We report the systematic control of morphology β-NaYF4:Yb,Er/Tm upconversion nanophosphors (UCNPs) from large spheres (37.9 nm) to rods (length = 60.1 nm, width 21.5 and hexagonal prisms 48.8 44.0 or small (14.0 by use a surfactant, an additive, lanthanide doping. Increasing ratio oleic acid (OA) 1-octadecene (ODE) caused decrease in size UCNPs, increasing OA/ODE above critical value particle shape change sphere rod. The length-to-width aspect (AR) nanorods (UCNRs) was finely manipulated...
Warm white LEDs with high color-rendering were achieved using Ca<sub>9</sub>LiY<sub>0.667</sub>(PO<sub>4</sub>)<sub>7</sub>:0.03Eu<sup>2+</sup>,0.10Mn<sup>2+</sup> phosphors.
Herein, we demonstrate video-rate color three-dimensional (3D) volumetric displays using elemental-migration-assisted full-color-tunable upconversion nanoparticles (UCNPs). In the heavily doped NaErF4:Tm-based core@multishell UCNPs, erbium migration was observed. By tailoring this through adjustment of intermediate shell thickness between core and sensitizer-doped second shell, red-green orthogonal luminescence (UCL) achieved. Furthermore, highly efficient red-green-blue UCL full-color...
High-power white light-emitting diodes (LEDs) are fabricated by combining blue LEDs and green (Ba,Sr)(2)SiO(4):Eu(2+) red CaAlSiN(3):Eu(2+) phosphors with varying phosphor geometry. The LED having separated the layer silicone gel between layers shows superior optical properties. luminous efficiency (eta(L)) is improved a decrease of reabsorption light owing to difference among refractive indices. very high eta(L) 51 lm/W color rendering index 95 under 350 mA. In addition, properties...
La 0.827 Al 11.9 O 19.09 : Eu 2 + , Mn showed three emission bands when excited by ultraviolet light. A blue originates from Eu2+, whereas both green and red emissions originate Mn2+. The luminescent mechanism is explained invoking the energy transfer of Eu2+→Mn2+ Mn2+(tetrahedralsite)→Mn2+(octahedralsite). This was confirmed faster decay times as donors. emitted color La0.827Al11.9O19.09:Eu2+,Mn2+ can be easily tailored to through variations Mn2+ content. white-light-emitting diode...
A novel, efficient, cost‐effective, and high‐level security performance anticounterfeit device achieved by plasmonic‐enhanced upconversion luminescence (UCL) is demonstrated. The plasmonic architecture consists of the randomly dispersed Ag nanowires (AgNWs) network, nanoparticles (UCNPs) monolayer, metal film, in which UCL enhanced a few tens, compared to reference sample, becuase modes lead concentration incident near infrared (NIR) light UCNPs monolayer. In configuration, both localized...
A new yellow-emitting γ-Ca2SiO4:Ce3+,Li+ phosphor was synthesized via a solid-state reaction. The showed strong yellow emission with wide bandwidth of 135.4 nm under blue light excitation. Absorption and photoluminescence measurements density functional theory calculations suggest that the luminescence can be attributed primarily to transitions 5d→4f (2F(7/2) 2F(5/2)) Ce3+ ions occupying Ca(1) sites in host crystal. White light-emitting diodes (LEDs) were fabricated by combining this LED,...
Red, green, blue, and natural white upconversion (UC) luminescence colors are realized from the tetragonal-structured LiGdF4-based core/triple-shell (C/T-S) nanophosphors (UCNPs) C/T-S UCNP-incorporated polymer composites. The LiYF4:Yb cores used as sensitized seeds for formation of LiGdF4:Yb,Tm UC shell followed by growth LiGdF4:Tb,Eu color tuning shell. Finally, LiYF4 inert is grown on core/shell/shell UCNPs, LiYF4:Yb/LiGdF4:Yb,Tm/LiGdF4:Tb,Eu/LiYF4 UCNPs exhibit enhanced luminescence....
Three-order enhanced upconversion luminescence from nanoparticles is suggested by way of a promising platform utilizing disordered array plasmonic metal nanoparticles. Its application toward highly sensitive NIR photodetectors discussed. As service to our authors and readers, this journal provides supporting information supplied the authors. Such materials are peer reviewed may be re-organized for online delivery, but not copy-edited or typeset. Technical support issues arising (other than...
This work reported on synthesis of highly efficient, color-pure green- and red-emitting non-Cd InP/ZnS core/shell quantum dots (QDs) their utilization as color converters for the fabrication display backlighting QD-based white light-emitting diode (LED). Green red QD emitters were first individually embedded into a transparent polymeric matrix polyvinylpyrrolidone resulting two free-standing composite plates then physically combined bilayered form. White QD-LED was fabricated by remotely...
We describe a metal nanodisk-insulator-metal (MIM) structure that enhances lanthanide-based upconversion (UC) and downshifting (DS) simultaneously. The was fabricated using nanotransfer printing method facilitates large-area applications of nanostructures for optoelectronic devices. proposed MIM is promising way to harness the entire solar spectrum by converting both ultraviolet near-infrared visible light concurrently through resonant-mode excitation. overall photoluminescence enhancements...
Abstract Perovskite has been actively studied for optoelectronic applications, such as photodetectors and light‐emitting diodes (LEDs), because of its excellent properties. However, ionic bonds the perovskite structure are vulnerable to chemicals, which makes incompatible with photolithography processes that use polar solvents. Such incompatibility hinders patterning device integration. Here, an all‐solution based cesium lead halide (Cs x Pb y Br z ) method is introduced in PbBr 2 patterned...
Dynamic manipulation of supramolecular self-assembled structures is achieved irreversibly or under non-physiological conditions, thereby limiting their biomedical, environmental, and catalysis applicability. In this study, microgels composed azobenzene derivatives stacked via π-cation π-π interactions are developed that electrostatically stabilized with Arg-Gly-Asp (RGD)-bearing anionic polymers. Lateral swelling RGD-bearing occurs cis-azobenzene formation mediated by...