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
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Yonghui Xu,Liang Zhang,Shuwen Yin,Xiudi Wu,Hongpeng You
Despite significant progress has been made in the luminescent materials for white light emitting diodes (WLEDs), it is still desirable to develop novel highly efficient phosphors with appropriate excitation and high visible emission for high color rendering WLEDs. In this study, we report a novel phosphor BaGa 2 Si 2 O 7 :Ce 3+ ,Tb 3+ (BGSO:Ce 3+ ,Tb 3+ ) with highly effective green luminescence. BGSO:Ce 3+ ,Tb 3+ phosphor represents a broad excitation band in the range of 300–400 nm and intense emission at approximately 542 nm with a high photoluminescence quantum efficiency of 76.4%. The structure, luminescence, and energy transfer from the Ce 3+ and Tb 3+ ions were investigated in detail. Moreover, the incorporation of Na + or K + ions into BGSO:Ce 3+ ,Tb 3+ for charge compensation can improve the emission intensity and thermal stability. Moreover, a near ultraviolet (n-UV) pumped prototype WLED device was fabricated and it exhibited bright warm-white light with CIE chromaticity coordinates of (0.3561, 0.3344), high color-rendering index (Ra=90.4), and low CCT (3330 K) upon 20 mA driving current. This work provides a new strategy to develop high-quality solid-state LED phosphors.
研究领域:
材料科学
·
光学工程
·
固体物理
·
发光材料
·
半导体器件
✓ 已验证
DOI
高影响因子
BULLETIN OF MATERIALS SCIENCE
·
2016
·Vol. 39
·期 1
·187-193
·
IF 0.895
CAO RENPING,QIN ZHENGDONG,JIANG SHENHUA,LIANG AIHUI,LUO ZHIYANG,YU XIAOGUANG
A series of CaNb 2 O 6 : x Sm 3+ (0 ≤
x
≤ 10 mol%) and CaNb 2 O 6 : Sm 3+ , Na + /B 3+ phosphors were synthesized by the solid-state reaction method in air. Their crystal structures and luminescence properties were investigated and analysed, respectively. Host CaNb 2 O 6 emitted blue light with excitation 270 nm. CaNb 2 O 6 : x Sm 3+ phosphors showed a systematically varied hue from blue to white by changing Sm 3+ ion concentration from 0 to 10 mol% with excitation of 270 nm and their chromaticity coordinates were the regions from (0.1665, 0.1767) to (0.2484, 0.2260). Luminescence properties of CaNb 2 O 6 : Sm 3+ phosphor were tuned and improved significantly by codoping B 3+ or Na + ions. Energy transfer between Nb \(_{\mathbf {2}}\textit {O}_{\mathbf {6}}^{\boldsymbol {2-}}\) group and Sm 3+ ion was observed and analysed via luminescence properties. The luminous mechanism was explained by energy level scheme and energy transfer process in CaNb 2 O 6 : Sm 3+ phosphor. The strong excitation band peaking at ∼ 407 nm indicated that the CaNb 2 O 6 : Sm 3+ , Na + /B 3+ phosphor has a potential application in white light-emitting diodes based on near-UV LED chip.
研究领域:
材料科学
·
无机化学
·
发光材料
·
固体物理
·
光电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2024
·Vol. 43
·期 10
·2100-2107
·
IF 5.2
Jing Yan,Junyu Hong,Xiaohui Li,Bojana Milićević,Lei Zhou,Chunyan Jiang,Mingmei Wu
Nowadays, high-quality phosphor-converted white light-emitting diodes (pc-WLEDs) ought to include cyan-emitting phosphors allowing for full-spectrum light similar to sunlight. Herein, we report a garnet-structured Ce 3+ -doped SrLu 2 Ga 1.5 Al 2.5 SiO 12 (SLGASO) phosphor that significantly compensates for the absence of cyan light, known as the “cyan cavity”. The SLGASO host crystallizes into a cubic structure with the I a 3 ¯ d space group. The cell parameters were determined using Rietveld refinement. Under 430 nm blue excitation, SLGASO:Ce 3+ emits intense cyan-green light in the 450–700 nm wavelength range. The representative SLGASO:0.07Ce 3+ phosphor has an internal quantum efficiency (IQE) of 95.4% and excellent thermal stability, remaining 92.7% of its initial emission intensity at 152 °C. After 155 d of immersion in water, the luminous intensity of SLGASO:0.07Ce 3+ remains constant, confirming its waterproofness. Furthermore, a pc-WLED device with luminous efficiency (LE) of 101.58 lm/W, color rendering index ( Ra ) of 91, correlated color temperature (CCT) of 4536 K, and Commission Internationale de L'Eclairage (CIE) chromaticity coordinates of (0.3555, 0.3390) was fabricated by combining as-prepared cyan-green-emitting SLGASO:0.07Ce 3+ , yellow-emitting Y 3 Al 5 O 12 :Ce 3+ (YAG:Ce 3+ ), and red-emitting (Ca,Sr)AlSiN 3 :Eu 2+ phosphors, as well as a 450 nm blue chip. These findings indicate that SLGASO:0.07Ce 3+ phosphor can bridge the cyan gap and improve the performance of as-fabricated full-visible-spectrum WLEDs.
研究领域:
材料科学
·
光学材料
·
固态照明
·
无机化学
·
光电子学
✓ 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
Advanced Optical Materials
·
2020
·Vol. 8
·期 22
·2001037
·
IF 8.286
Dongjie Liu,Xiaohan Yun,Guogang Li,Peipei Dang,Maxim S. Molokeev,Hongzhou Lian,Mengmeng Shang,Jun Lin
Highly efficient cyan-emitting phosphor materials are indispensable for closing the cyan gap in spectra of the traditional phosphor-converted white light-emitting diodes (WLEDs) to achieve high-quality full-spectrum white lighting. In this work, bright cyan-emitting Ca 3 Ga 4 O 9 (CGO):0.02Bi 3+ ,0.07Zn 2+ phosphor is developed to bridge the cyan gap. Such a Bi 3+ ,Zn 2+ codoping enhances the cyan emission of CGO:0.02Bi 3+ by 4.1 times due to the influence of morphology and size of phosphor particles, charge compensation and lattice distortion. Interestingly, codoping La 3+ ions into the current system can achieve a photoluminescence tuning of CGO:0.02Bi 3+ from cyan to yellowish-green by crystallographic site engineering. Besides, Bi 3+ –Eu 3+ energy transfer is successfully realized in CGO:0.02Bi 3+ ,0.07Zn 2+ , n Eu 3+ phosphors and the emission color tuning from cyan to orange is observed. The investigation of thermal quenching behaviors reveals that the incorporation of Zn 2+ and La 3+ improves the thermal stability of CGO:0.02Bi 3+ . Finally, CGO:0.02Bi 3+ ,0.07Zn 2+ ,0.10Eu 3+ phosphor is employed to obtain a single-phased warm WLED device. A full-spectrum WLED device with remarkable color rendering index (Ra) of 97.4 and high luminous efficiency of 69.72 lm W −1 is generated by utilizing CGO:0.02Bi 3+ ,0.07Zn 2+ phosphor. This result suggests the important effect of CGO:0.02Bi 3+ ,0.07Zn 2+ phosphor on closing the cyan gap, providing new insights of cyan-emitting phosphors applied in full-spectrum white lighting.
研究领域:
材料科学
·
光学工程
·
固体物理
·
无机化学
·
光电子学
·
照明技术
✓ 已验证
DOI
高影响因子
DYES AND PIGMENTS
·
2017
·
IF 3.473
Yijun Zhang,Jiaqi Zhang,Junwen Zhang,Sai Lin,Yunyun Huang,Rongrong Yuan,Xiaojuan Liang,Weidong Xiang
A novel gold-carbon dots (GCDs) exhibiting relatively high luminescence have been successfully synthesized by a facile solution cast method. Intriguingly, colloidal Au nanoparticles (Au NPs) present an enhancement effect on the photoluminescence of CDs, which can be attributed to the metal enhanced fluorescence (MEF) included two cooperative mechanisms and near-field interactions. Significantly, the 1.5–3 fold enhancement was obtained in the vicinity of Au NPs. The formation mechanism and chemical structure of the as-prepared GCDs were verified by a series of characterization techniques, such as high-resolution transmission electron microscope (HRTEM), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The GCDs with optimal fluorescence was acquired by varying volume ratio of colloidal Au NPs to CDs, rendering bright visible light under 460 nm excitation and high quantum yield (QY) of 39%. Given that, a simple spin coating technology was developed for fabricating GCDs film composed of GCDs solution and quartz glass. Subsequently, GCDs-based white light emitting diodes (white LED) was designed through integrating blue LED chips with the yellow light-emitting GCDs film. In addition, the GCDs film at appropriate thickness possesses excellent optical performances with the corresponding optimized color coordinate (CIE) of (0.33, 0.36), the color rendering index (CRI) of 78.2, correlated color temperature (CCT) of 5653 K, and the luminous efficiency (LE) approaching to 43.75 lm W −1 . These superior results demonstrate that GCDs constitute a versatile and effective route for achieving high-performance white LED.
研究领域:
材料科学
·
纳米技术
·
光电子学
·
发光材料
·
半导体器件
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Yaping You,Ya Zheng,Zesheng Pan,Yunluo Wang,Tianrui Zhou,Minghui Wang,Haijie Chen,Wan Jiang,Lianjun Wang
White light-emitting diode (WLED) has been widely used as solid-state lighting in recent years, with the advantages of energy saving, high luminous efficiency , and safety. Red phosphors are crucial to the color rendering index of WLED, and Eu 3+ -activated red phosphors can significantly improve the chromaticity performance of WLED. In this work, a series of new orange-red emitting BaLiZn 3 (PO 4 ) 3 : Eu 3+ phosphors were synthesized through high-temperature solid-state reaction method. The phase composition , crystal structure, morphology and photoluminescence properties of BaLiZn 3 (PO 4 ) 3 : Eu 3+ samples were investigated. The phosphors can be effectively excited by the violet light at 394 nm and emit orange-red lights corresponding to the electric dipole transition (5D 0 →7F 1 ) at 594 nm. The optimal doping concentration of Eu 3+ ions was about 5 mol%. The concentration quenching was caused by the electric dipole-dipole interaction between Eu 3+ ions. Temperature-dependent PL spectra indicate that BaLiZn 3 (PO 4 ) 3 : Eu 3+ has excellent emission and color stability at high temperatures. The color coordinates were calculated and fall in the orange-red luminescent area. The color purity is about 98.3 %, and the correlated color temperature is 1710K. These results indicate that the new orange-red phosphor BaLiZn 3 (PO 4 ) 3 : Eu 3+ has potential application prospects in WLED.
研究领域:
材料科学
·
发光材料
·
固体照明
·
无机化学
·
光电子学
✓ 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
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2021
·
IF 4.539
Yongsheng Yang,Siyuan Tang,Da Chen,Changxing Wang,Bingli Gu,Xiameng Li,Feng Xie,Gang Wang,Qinglei Guo
In this study, red-emission graphene quantum dots (R-GQDs), with tunable emission wavelength , are synthesized and explored for applications in trace water sensing, white light emitting diodes (WLEDs) and information encryption . Systematic experiments and characterizations demonstrate that the as-fabricated R-GQDs possess homogeneous size, good crystallinity and high doping concentration of nitrogen and oxygen. Moreover, tunable multicolor light emissions of R-GQDs are demonstrated by simply adjusting the polarity of surrounding solvents. As a result, solid-state fluorescence films are successfully fabricated to construct a high-quality WLED, with the CIE (Commission International d′Eclairage) coordinates (0.352, 0.380) and color temperature of 5121 K. Besides, the water quenchable fluorescence of R-GQDs enables the fabrication of a trace water sensing platform, with the low detection limit of 0.034%. Finally, the potential of our prepared R-GQDs for the application in color visual information encryption is developed. This study may pave the way for the development of GQDs, especially in optically sensing, optoelectronics and anti-counterfeiting technology.
研究领域:
纳米材料学
·
光学传感
·
光电子学
·
分析化学
·
防伪技术
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2018
·Vol. 47
·期 26
·8697-8705
·
IF 4.099
Yang Ding,Jie Liu,Ming Zeng,Xishu Wang,Junli Shi,Weili Wang,Yanru Miao,Xibin Yu
Rare earth (RE3+)-doped NaY(MoO4)2 nanocrystals are efficient materials for realizing multicolor emission, which plays an important role in displays, W-LEDs, solar cells and biolabeling. Up to now, research on the multicolor tuning properties of RE3+-doped NaY(MoO4)2 nanoparticles has mostly focused on traditional preparation routes such as the hydrothermal method and sol–gel process. However, the products obtained using these methods are usually large in size (on the micron/submicron scale) and agglomeration problems are inevitable. With the development of nano optoelectronic devices and bioluminescence labeling, there is an urgent need to find an efficient method to prepare nanoscale, monodispersed and NaY(MoO4)2:RE3+ nanocrystals (NCs) with good crystallinity and stronger emission properties. In this work, we demonstrate a simple, fast, reproducible and one-step synthesis of NaY(MoO4)2:Eu3+ NCs with sizes varying from 1–20 nm via a ligand-assisted reprecipitation strategy. The reaction mechanism and emission intensities of NaY(MoO4)2:Eu3+ NCs with various morphologies have been discussed in detail. Furthermore, Tb3+ and Eu3+ ion co-doped NaY(MoO4)2 NCs were also prepared, and various emission colors were obtained and tuned from red, orange-red, yellow and yellow-green to green. Energy transfer between the Tb3+ and Eu3+ ions in the NaY(MoO4)2 host matrix has also been demonstrated. Finally, a highly efficient and stable NaY(MoO4)2:0.05Tb,0.04Eu NC-based W-LED device was built, which indicates the promising future application for this material in the field of lighting. The tunable multicolour emission, ease of preparation and nanosize reveal that NaY(MoO4)2:RE3+ NCs have a potential application in full color displays and W-LEDs.
研究领域:
材料科学
·
纳米技术
·
光学材料
·
无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）