DYES AND PIGMENTS
·
2023
·
IF 4.5
Fuhua Gao,Wasim Ullah Khan,Zhiyuan Cheng,Waheed Ullah Khan,Iqtidar Ahmad,Zhiqi Ye,Shenghong Yang,Yueli Zhang
Broadband near-infrared (NIR)-emitting materials have critical applications in biology, medical detection, and NIR night-vision. However, developing NIR phosphors with promising optical properties and excellent thermal stability is a great challenge for research. In this work, a novel NIR phosphor Cr 3+ and Yb 3+ doped CaSc 2 O 4 (CSO) is an evolving NIR emitting phosphor with decent optical properties , boosted emission intensity, and thermal stability that makes it a promising candidate with potential applications in NIR-LED and infrared night-vision. The implications of the fundamental electronic structure of CSO, including valence-band (VB) and conduction-band (CB) orbital character, are investigated. Under blue light excitation, CSO:Cr 3+ is settled with pure broadband NIR emissions (max = 920 nm, FWHM (full width at half maximum) = ∼310 nm) and good thermal stability . The occupation of two selectable lattice sites of Cr 3+ in CSO is discussed in detail. Furthermore, emission enhancements of samples are done by Cr 3+ and Yb 3+ codoping, effectively broadening FWHM to 351 nm and reducing thermal quenching. The energy transfer (ET) routes in CSO:Cr 3+ ,Yb 3+ are investigated based on PL lifetime and comprehensive kinetic ET model, revealing that the PL enhancements by Cr 3+ and Yb 3+ codoping mainly originate from the ET from Cr 3+ to Yb 3+ emitters with more efficient and thermally stable. Finally, an InGaN-LED device encapsulated using CSO:0.01Cr 3+ and CSO:0.01Cr 3+ ,0.01 Yb 3+ phosphor was fabricated. The fabricated NIR pc-LEDs are excellent candidates for NIR light sources in biological imaging and NIR night vision.
研究领域:
光学材料
·
生物医学成像
·
光电子学
·
无机发光材料
·
红外技术
·
固态照明
·
纳米生物技术
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2024
·
IF 5.3
C. Wang,X.Z. Zheng,L. Yue,P.J. Xia,M. Xu,W.B. Dai
The exploration of stable/efficient phosphor for n -UV chip pumped white light-emitting diodes ( w LEDs) remains an arduous task. Herein, a novel series of color tunable Eu 2+ /Tb 3+ /Sm 3+ tridoped Sc-based cyclosilicate phosphors (KBaScSi 3 O 9 : Eu 2+ /Tb 3+ /Sm 3+ ) have successfully designed and obtained via facile solid-state reaction based on comprehensive consideration of rigidly structural network of host, weak electron-phonon coupling strength and spectral adjustability of codopants via energy transfer (ET). The crystallographic occupancies of Eu, Tb and Sm primary in Ba/K, Ba and Ba sites in the monoclinic host, respectively were determined on the basis of the Rietveld refinements and crystal chemistry rules. The photoluminescence (PL) properties were systematically investigated in conjunction with structural analyses, implying that the ‘warm’ white light with excellent thermal stability is stemmed from combination of optimized blue (Eu 2+ ), green (Tb 3+ ) and red (Sm 3+ ) emissions via Eu → Tb → Sm ET strategy. Interestingly, Tb ions play both roles of green light luminescent center and ET bridge to achieve cascade ET for connecting Eu/Sm ion pairs because of the adverse metal-metal charge transfer (MMCT) effect (Eu 2+ + Sm 3+ → Eu 3+ + Sm 2+ ). Furthermore, the phosphor-converted w LEDs (pc- w LEDs), by encapsulating the optimal KBS: 4 %Eu/4 %Tb/6 %Sm with commercial n -UV LED chip, show high thermal stability with satisfactory electroluminescence (EL) performances. These results indicate the KBS: Eu/Tb/Sm phosphors are potential candidates for application in high power n -UV pumped pc- w LEDs.
研究领域:
材料科学
·
发光材料
·
固态照明
·
无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2014
·Vol. 26
·期 2
·884-890
·
IF 1.966
Li Rui,Wang Yan-ze,Mao Zhi-yong,Wang Da-Jian
A remote phosphor coating by using Sr 3 (Al,Si)(O, F) 5 :Ce 3+ (SASF:Ce 3+ ) on glass substrate was prepared by a simple and convenient screen printing method. The crystalline phase and the distribution of SASF:Ce 3+ crystals in coating were investigated by XRD and SEM, respectively. The scattering light and absorption light properties of remote phosphor coating with different thicknesses were discussed through Lambert–Beer’s law. The relationship between luminous efficiency and absorption coefficient was demonstrated. White light emitting diode prototype fabricated with blue chip and the prepared patterned SASF:Ce 3+ remote phosphor in this work showed excellent performances, opening a cost-effective process to generate planar white light.
研究领域:
材料科学
·
光学工程
·
发光材料
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固态照明
·
功能涂层
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2023
·
IF 5.4
Zhihao Zhang,Huimin Li,Ran Pang,Wenjing Wang,Da Li,Lihong Jiang,Su Zhang,Hongjie Zhang
Phosphor-converted light emitting diodes (pc-LEDs) are essential for current lighting and display areas because of their unique properties of being uncomplicated, durable and economical. In previous studies, Pr 3+ doped red-emitting phosphors have attracted enormous research interest due to their high color purity. However, their photoluminescence excitation (PLE) spectra are always hard to be combined with LED chips. This mismatch is a great obstacle to achieve Pr 3+ phosphors utilizing in LED devices. Here, to circumvent this issue, Pr 3+ -doped Ca 3 MgTiGe 3 O 12 (CMTG) red-emitting phosphor was optimized with PLE band shifting from 330 nm to 360 nm after tuning with Bi 3+ co-doping based on the structure and phosphorescence properties. The chip-matched excitation makes it a good candidate for white LEDs (wLEDs) fabrication to improve the output quality of device. Meanwhile, the high color purity of 93.02 % was obtained, which is conducive to widening the color gamut of backlight display applications. The photoluminescence (PL) spectra, fluorescence lifetime, and X-ray photoelectron spectroscopy (XPS) analysis were employed and discussed in detail to explain the role of Bi 3+ played in the system. Finally, wLEDs were fabricated with CMTG:Pr 3+ , Bi 3+ , showing a high color rendering index (Ra) of 94.4. And the color gamut covers ∼80 % of the National Television System Committee (NTSC) standard, suggesting great potential for applications of wLEDs and backlight display.
研究领域:
材料科学
·
发光材料
·
固态照明
·
显示技术
·
无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
Materials Today Chemistry
·
2022
·
IF 7.613
S. Wu,Y. Fu,Q. Liu,P. Xiong,D. Wang,G. Zhang,S. Yuan,Y. Chen
Developing highly efficient cyan-emitting fluorescent materials is essential to bridge the cyan gap in phosphor-converted white light-emitting diodes for full-spectrum white illumination. Here, a Bi-doped cyan phosphor has been reported to solve this gap. The phase purity, photoluminescence emission/excitation spectra, concentration quenching, lifetime decay curves, and temperature-dependent photoluminescence emission spectra were systematically investigated. SrLaGaO 4 :Bi 3+ exhibits a broad excitation band (250–400 nm), which matches with the emission of a commercial near-ultraviolet light-emitting diode chip. The cyan light peaked at 475 nm is observed, which is attributed to the 3 P 1 → 1 S 0 transition of Bi 3+ . The thermal quenching experiment was performed, and the activation energy was calculated as 0.36 eV. Finally, full-spectrum white light-emitting diode devices were fabricated using SrLaGaO 4 :Bi 3+ phosphors, commercial blue BaMgAl 10 O 17 :Eu 2+ phosphor, green (Ba, Sr) 2 SiO 4 :Eu 2+ phosphor, and red CaAlSiN 3 :Eu 2+ phosphor, which displayed an International Commission on an illumination coordinate of (0.3732, 0.3850), a correlated color temperature of 4290 K, and a color rendering index of 93.2 at a drive current of 20 mA. This result indicates that SrLaGaO 4 :Bi 3+ plays an essential role in bridging the cyan gap, providing new inspiration for applying cyan-emitting phosphors in full-spectrum white lighting.
研究领域:
材料科学
·
光学工程
·
固态照明
·
发光材料
·
无机化学
✓ 已验证
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2021
·Vol. 40
·期 11
·1691-1698
·
IF 3.712
Qingsong Hu,Zaifa Pan,Guijie Liang
White light-emitting diodes (WLEDs) fabricated by single-phase full color emitting phosphor are an emerging solution for health lighting. The crystallographic site occupation of activators in a proper host lattice is crucial for sophisticated design of such phosphor. Here, we report a high quality white light-emitting phosphor Ba 2 Ca(BO 3 ) 2 :Ce 3+ (K + ),Eu 2+ ,Mn 2+ with spectral distribution covering whole visible region. Blue light emission originates from Ce 3+ ions occupying preferentially Ba 2+ site by controlling synthesis conditions. Green and red lights are obtained from Eu 2+ occupying Ba 2+ (and Ca 2+ ) site and Mn 2+ occupying Ca 2+ site, respectively. In this triple-doped phosphor, strong red emission with a low concentration of Mn 2+ is realized by the efficient energy transfer from Ce 3+ and Eu 2+ to Mn 2+ . Furthermore, high quality white light is accomplished by properly tuning the relative doping amount of Ce 3+ (K + )/Eu 2+ /Mn 2+ based on efficient simultaneous energy transfer. The results indicate that Ba 2 Ca(BO 3 ) 2 :Ce 3+ (K + ),Eu 2+ ,Mn 2+ is a promising white light-emitting phosphor in WLEDs application.
研究领域:
材料科学
·
无机化学
·
发光材料
·
固态照明
·
能源材料
✓ 已验证
DOI
高影响因子
SOLID STATE COMMUNICATIONS
·
2017
·
IF 1.554
Jingjing Chen,Yang Zhao,Guanghao Li,Zhiyong Mao,Dajian Wang,Lijian Bie
In this paper, facile synthesis of CaAlSiN 3 :Ce 3+ yellow-emitting phosphors under atmospheric pressure at a moderate temperature and their photoluminescent properties are reported. The prepared CaAlSiN 3 :Ce 3+ phosphors exhibit a broad yellow emission band positioned at 580 nm and covering a bandwidth of 150 nm. The thermal stability of CaAlSiN 3 :Ce 3+ phosphors shows obvious superiority than the commercial YAG: Ce 3+ phosphor, indicating its promising application prospect in power LEDs . In addition, the enhancement of red-light component for CaAlSiN 3 :Ce 3+ phosphor is demonstrated by co-doping Eu 2+ ions. This study offers a facile route to prepare CaAlSiN 3 :Ce 3+ yellow-emitting phosphors, which may be used as a promising candidate for high performance white LEDs .
研究领域:
材料科学
·
发光材料
·
无机化学
·
固态照明
·
光电功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2017
·
IF 2.686
Haoyue Hao,Hongyu Lu,Guanghong Ao,Yinglin Song,Yuxiao Wang,Xueru Zhang
The nearly pure green and red emissions of Ho 3+ /Yb 3+ co-doped Gd 2 (MoO 4 ) 3 were realized by tri-doping Eu 3+ and Ce 3+ , respectively. The Ho 3+ /Yb 3+ co-doped Gd 2 (MoO 4 ) 3 powder, radiating intense green and red emissions, was prepared by a typical sol-gel method. Under the excitation of 980 nm laser, the red-to-green ratio was tuned from 0.2 to 4 as the concentration of Eu 3+ changed from 6 to 0 mol%, attributed to the energy transfer processes between Ho 3+ and Eu 3+ . Meanwhile, the red-to-green ratio altered from 4 to 20 as the concentration of Ce 3+ changed from 0 to 20 mol% via the cross relaxing processes between Ho 3+ and Ce 3+ . The prepared phosphors, possessing large tuning range of red-to-green ratio and resisting high temperature, can be potentially applied to colorful display and solid-state lighting.
研究领域:
材料科学
·
光学材料
·
光子学
·
固态照明
·
显示技术
✓ 已验证
DOI
高影响因子
ACS Applied Optical Materials
·
2023
·
IF 0
Zhennan Wang,Yi Wei,Zhiliang Ren,Wei Wang,Dong Tu,Guogang Li
Near-infrared (NIR) light serves a key role in many potential applications such as food analysis, biomedical devices, night vision, and so on. As an important component of NIR phosphor-converted light-emitting diodes (pc-LEDs), the adjustment of emission peak position and spectral width of Cr3+-doped phosphors is still considered to be a crucial challenge. Herein, the two emissions at 740 nm from [Cr1O6] and 830 nm from [Cr2O4] were realized to broaden the emission band in the Al2.26Ge0.74O4.87:Cr3+ (AGO:Cr3+) phosphor. Moreover, with increasing Cr3+-doped concentration, the crystal field strength decreases and energy transfer from [Cr1O6] to [Cr2O4] is enhanced. The emission peak originating from [Cr2O4] gradually becomes dominant, resulting in a spectral red shift and broadening. The optimized AGO:0.7% Cr3+ phosphor shows remarkable thermal stability, of which the integrated intensity at 373 K keeps 86% of the initial intensity at 298 K. Under 405 nm excitation, the internal quantum efficiency could reach 70% and the external quantum efficiency was measured to be 23%. The application of night vision can be implemented based on the AGO:Cr3+-fabricated NIR pc-LED. This work achieves simultaneous modulation of luminescence color and spectral width by controlling the Cr3+-doped concentration, which provides a feasible strategy for NIR emission adjustment.
研究领域:
材料科学
·
光学材料
·
固态照明
·
光子学
·
发光
✓ 已验证
DOI
INORGANIC CHEMISTRY
·
2023
·
IF 4.6
Liping Song,Sisi Liang,Wendong Nie,Xianguo He,Jie Hu,Fulin Lin,Haomiao Zhu
Recent decades have witnessed a major development in broadband near-infrared (NIR)-emitting phosphors because of their potential applications in real-time nondestructive examination. These applications require the emission spectra of phosphors to be as broad as possible for efficient performance. Therefore, a blue-light excited LiInF4: Cr3+ phosphor with a NIR emission covering 700–1400 nm is successfully synthesized. Under 470 nm excitation, it shows broadband emission peaked at 980 nm with the full-width at half maximum of 210 nm. The structure and crystal field environment are investigated in detail, and the LiInF4: Cr3+ possesses a weak crystal field strength and strong electron–phonon coupling. An efficient NIR phosphor-converted light-emitting diode (pc-LED) is fabricated by the prepared LiInF4: Cr3+ phosphor and commercial blue diode chip, generating a NIR radiant flux of 5.54 mW at 150 mA drive current. Finally, the NIR pc-LED is successfully applied to identify the blood vessel distribution of the hand. This work suggests the potential of LiInF4: Cr3+ phosphor in applications.
研究领域:
材料科学
·
光学材料
·
固态照明
·
光子学
·
生物医学成像
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2021
·Vol. 50
·期 36
·12592-12606
·
IF 4.39
Yao Wang,Ning Guo,Yanmei Xin,Jing Li,Ruizhuo Ouyang,Baiqi Shao,Yuqing Miao
The synthesis conditions of most phosphors doped with lanthanide ions with d–f transition require a reducing atmosphere. The doping Bi3+ ions selected in this study perfectly avoid this requirement, and they are environmentally friendly and safe. Nevertheless, the spectral tuning of Bi3+ is a great challenge that limits its application. Herein, by regulating the value of x in the new solid solution Sr2+xLa1−xGaO5−xFx, the luminescence of Bi3+ is well promoted. Through an excitation-driven strategy, the emission peak position of Bi3+ is redshifted, and the luminescence of trivalent bismuth is successfully adjusted, which can also be applied to anti-blue lighting. In addition, we constructed a Bi3+–Eu3+ dual luminescence system, and, regardless of changes in the Bi3+/Eu3+ concentration or excitation wavelength, a single matrix white light phosphor was realized. Through calculations, the activation energy of the phosphor doped with 2.5%Eu3+ was found to be 0.257 eV, which is higher than the activation energy of some common compounds. This indicates that the phosphor has good application prospects in the field of solid-state lighting. It is worth noting that based on the different thermal response behaviors of Bi3+ and Eu3+, when the Eu3+ content is fixed at 1%, the maximum relative sensitivity of the optical thermometer based on its fluorescence intensity ratio is about 1.46% K−1 at 383 K, which is higher than that of Bi3+ and Eu3+ co-doped phosphors previously reported. We also obtained a high absolute sensitivity of 0.00139 K−1 at 403 K. Therefore, we also studied the thermal sensitivity of Bi3+ and Er3+ co-doped solid solutions. The results show that this solid-solution phosphor has far-reaching application prospects in the temperature sensing field.
研究领域:
材料科学
·
发光材料
·
固态照明
·
光学温度传感
·
荧光粉化学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2023
·
IF 4.6
Yi Zhang,Zhexuan Gao,Yingguang Li,Shuyang Chen,Mingxiao Han,Jie Li,Qihao Zhang,Yang Shen,Degang Deng,Shiqing Xu
The La2LiSbO6: xCr3+ phosphors were synthesized by means of a high-temperature solid-phase method. Based on the differences in ionic radius, valence state, and formation energy, the substitution sites of Cr3+ ions are discussed in detail. The optimized doping concentration of Cr3+ is determined to be 0.01. Under 517 nm excitation, the La2LiSbO6: 0.01Cr3+ phosphor presents a wide emission band (from 700 to 1350 nm) with a peak centered at 952 nm. Additionally, its corresponding full width at half-maximum is 155 nm, and the internal quantum efficiency reaches 62.4%. Meanwhile, the emission intensity of the La2LiSbO6: 0.01Cr3+ phosphor at 373 K is about 63.7% of that at room temperature, exhibiting good thermal stability. Aiming to fabricate a near-infrared phosphor-converted light-emitting diode device, the La2LiSbO6: 0.01Cr3+ phosphor is mixed with epoxy adhesive and cured on a green light-emitting diode chip. Under the irradiation of the fabricated light-emitting diode device, fruits and writing in the dark environment can be captured by a near-infrared camera. Hence, the La2LiSbO6: 0.01Cr3+ phosphor is promising for night vision.
研究领域:
材料科学
·
光学材料
·
固态照明
·
光子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）