A5079045956- Luminescence Properties of Advanced Materials
- Perovskite Materials and Applications
- Microwave Dielectric Ceramics Synthesis
- Advanced Photocatalysis Techniques
- Ga2O3 and related materials
- Inorganic Fluorides and Related Compounds
- Radiation Detection and Scintillator Technologies
- Gas Sensing Nanomaterials and Sensors
- Inorganic Chemistry and Materials
- Quantum Dots Synthesis And Properties
- Ammonia Synthesis and Nitrogen Reduction
- Solid-state spectroscopy and crystallography
- Luminescence and Fluorescent Materials
- Solid State Laser Technologies
- Advanced Battery Materials and Technologies
- Semiconductor materials and devices
- ZnO doping and properties
- Thermal Expansion and Ionic Conductivity
- Electrocatalysts for Energy Conversion
- Advancements in Battery Materials
- Catalytic Cross-Coupling Reactions
- Terahertz technology and applications
- Optical properties and cooling technologies in crystalline materials
- Advanced Computing and Algorithms
- Energetic Materials and Combustion
Academia Sinica
2023-2025
Research Center for Applied Science, Academia Sinica
2022-2024
National Taiwan University
2014-2023
The near-infrared (NIR) light source is desirable for real-time nondestructive examination applications, which include the analysis of foodstuffs, health monitoring, iris recognition, and infrared cameras. emission spectra such an should also be as broad possible effective performance, in view fact that absorption reflection by organic elements present foodstuffs human fall blue NIR regions electromagnetic spectrum, respectively. In this letter, a light-emitting diode (LED) excitable super...
Red phosphors AMF6:Mn(4+) (A = Na, K, Cs, Ba, Rb; M Si, Ti, Ge) have been widely studied due to the narrow red emission bands around 630 nm. The different of zero-phonon line (ZPL) may affect color rendering index white light-emitting diodes (WLED). primary reason behind emergence and intensity ZPL, taking KNaSiF6:Mn(4+) as an example, was investigated here. effects pressure on crystal structure luminescence were determined experimentally theoretically. increase band gap, shift spectrum blue...
Optimizing properties of phosphors for use in white-light-emitting diodes (WLEDs) is an important materials challenge. Most have a low level lattice disorder due to mismatch between the host and activator cations. Here we show that deliberate introduction high levels cation leads significant improvements quantum efficiency, stability thermal quenching, emission lifetime Sr1.98–x(Ca0.55Ba0.45)xSi5N8:Eu0.02 (x = 0–1.5) phosphors. Replacing Sr by (Ca0.55Ba0.45) mixture with same average radius...
A new class of Mn<sup>4+</sup>activated alkali-metal hexafluoride red phosphors are emerging for white light-emitting diodes because their sharp line<sup>2</sup>E<sub>g</sub>→<sup>4</sup>A<sub>2g</sub>emissions (600–650 nm) excited by irradiation of<sup>4</sup>A<sub>2g</sub>→<sup>4</sup>T<sub>1g</sub>(320–380 and<sup>4</sup>A<sub>2g</sub>→<sup>4</sup>T<sub>2g</sub>(380–500 transitions.
A one-step approach to synthesize Na<sub>2</sub>SiF<sub>6</sub>:Mn<sup>4+</sup>and K<sub>2</sub>SiF<sub>6</sub>:Mn<sup>4+</sup> red phosphors by co-precipitation is reported in this paper.
Portable near-infrared (NIR) light sources are in high demand for applications spectroscopy, night vision, bioimaging, and many others. Typical phosphor designs feature isolated Cr3+ ion centers, it is challenging to design broadband NIR phosphors based on Cr3+–Cr3+ pairs. Here, we explore the solid-solution series SrAl11.88–xGaxO19:0.12Cr3+ (x = 0, 2, 4, 6, 8, 10, 12) as featuring pairs evaluate structure–property relations within series. We establish incorporation of Ga...
Recently, infrared (IR) light-emitting diodes (LEDs) have attracted considerable interest in the research field worldwide. IR phosphors, basic materials utilized LEDs, become a hotspot as well. Here, we introduce high-quantum-efficiency ScBO3:Cr3+ phosphor, which provides spectral range of emission from 700 to 1000 nm with peak maximum at 800 nm. Electron paramagnetic resonance spectroscopy, high element selectivity, was used elucidate unusual small photoluminescence spectrum. Phonon...
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTHigh Color Rendering Index of Rb2GeF6:Mn4+ for Light-Emitting DiodesWei-Lun Wu†, Mu-Huai Fang†, Wenli Zhou†, Tadeusz Lesniewski‡, Sebastian Mahlik‡, Marek Grinberg‡, Mikhail G. Brik§#∥, Hwo-Shuenn Sheu⊥, Bing-Ming Cheng⊥, Jing Wang∇, and Ru-Shi Liu*†¶View Author Information† Department Chemistry, National Taiwan University, Taipei 106, Taiwan‡ Institute Experimental Physics, Faculty Mathematic, Physics Informatics, Gdańsk Wita Stwosza 57,...
We aim to conduct a complete study on the unexpected structure evolution behavior in Cr3+-doped phosphors. A series of Ga2–xScxO3:Cr3+ phosphors are successfully synthesized and confirmed through structural studies, while lattice parameters change unexpectedly. The unique partial substitution (∼87%) Sc3+ octahedral site is demonstrated via Rietveld refinement. Therefore, bond valence sum calculation explains reason for this particular concentration. photoluminescent bandwidth...
A near-infrared Ga<sub>2</sub>O<sub>3</sub>:Cr<sup>3+</sup>phosphor and the controlling of phytochrome.
Light-emitting diodes (LEDs) are widely used around the world. Scientists attempting to develop LED devices that not only have high brightness but also a color rendering index (CRI). Phosphor materials play important roles in tuning and optimizing final luminescent spectrum. Narrow-band emission phosphors must be incorporated into chips achieve CRI efficacy. From this perspective, we introduce discuss key points narrow-band Three sets of phosphor examples, namely, Eu-doped (Ba,Sr)Si2O2N2,...
Two types of infrared fluoride phosphors, Cr3+-doped K3AlF6 and K3GaF6, were developed in this research. The K3Al1–xF6:xCr3+ K3Ga1–yF6:yCr3+ phosphors proven to be pure phase via X-ray diffraction refinement, which demonstrated that the procedure can applied large-scale production. Electron paramagnetic resonance measurements indicated Cr3+ ions cubic with respect noncubic are coupled better K3GaF6 than K3AlF6. main differences between these two site symmetry pressure behavior spectra,...
Mn4+ -doped fluoride phosphors have been widely used in wide-gamut backlighting devices because of their extremely narrow emission band. Solid solutions Na2 (Six Ge1-x )F6 :Mn4+ and (Gey Ti1-y were successfully synthesized to elucidate the behavior zero-phonon line (ZPL) different structures. The ratio between ZPL highest intensity υ6 phonon sideband exhibits a strong relationship with luminescent decay rate. First-principles calculations are conducted model variation structural electronic...
A new concept called "full-spectrum lighting" has attracted considerable attention in recent years. Traditional devices are usually combined with ultraviolet-light-emitting diode (LED), red, green, and blue phosphors. However, a cyan cavity exists the 480-520 nm region. Hence, phosphors needed to compensate for cavity. (Sr,Ba)5(PO4)3Cl:Eu2+ feature an extremely unique tunable photoluminescence spectrum. Nevertheless, tuning mechanisms of these remain unclear. In this study, we elucidate...
A new Rb<sub>2</sub>SiF<sub>6</sub>:Mn<sup>4+</sup>phosphor has been successfully synthesized through a one-step co-precipitation method.
Narrow-band Mn4+-doped fluoride phosphors have become a research hotspot worldwide. In this study, we propose integrated surface modification processes to enhance the performance and stability of luminescence properties K2TiF6:Mn4+ (KTF) phosphor. These process are applied in initial synthesis step, coating as-synthesized powder post-treatment process, during application phosphor white-light-emitting diode (WLED) device. Surface etching is conducted remove impurities small particles KTF....
Mini-light-emitting diodes (mini-LEDs) are regarded as a promising light source for future high-end electronic products. Phosphors with small size and high efficiency have been reported to achieve this goal. Here, we demonstrate that an easily synthesized Ga2O3:Cr3+-embedded mesoporous silica nanoparticle (GOC@MSN) is outstanding nanophosphor superb internal quantum (91.4%) good thermal stability. Structural studies determined the mesostructure intermolecular transfer of free electrons....
Searching for narrow-band red-emitting and thermally stable phosphors is the ultimate strategy toward enhanced performance of phosphor converted light emitting diodes (pc-LED). The red emission assured by nitride host because its relatively more covalent character than oxides sulfides; however, narrow attributed to crystallographic, morphological, electronic considerations. symmetric coordination site ensures equal ligand effect in all direction fits well with configuration Eu2+ f orbitals...
Research on light-emitting diodes has considerably progressed over the years, so they are expected to possess excellent color rendition and high luminescent intensity. Cuboid-based red-nitride phosphors highly promising because characterized by a narrow-band emission property, low energy waste, thermal stability. However, existing nitride have limited diversity of lack other anions. A new series cuboid-based oxide called alkali lithosilicates is attracting considerable research attention...
Narrow-band green-emitting phosphor β-SiAlON:Eu has been widely used in advanced wide-gamut backlighting devices. However, the origins for unusual sharp lines photoluminescence emission at room temperature and tunable narrow-band-emission tailored by reducing Al–O are still unclear. Here, presence of sharp-line fine structure spectra is mainly due to purely electronic transitions (zero phonon lines), their vibronic repetitions resulting from multimicroenvironment around Eu2+ ions that...
Abstract In this study, a series of Sr(LiAl 3 ) 1− x (SiMg N 4 :Eu 2+ (SLA‐SSM) phosphors were synthesized by solid‐solution process. The emission peak maxima SLA‐SSM range from 615 nm to 680 nm, which indicates structural differences in these materials. 7 Li solid‐state NMR spectroscopy was utilized distinguish between the Li(1)N and Li(2)N tetrahedra SLA‐SSM. Differences coordination environments two Sr sites found explain unexpected luminescent properties. Three discernible morphologies...