JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Xiaoya Bu,Yan-gai Liu,Jian Chen
A series of original tunable-luminescence phosphors K 3 Lu(PO 4 ) 2 : Tb 3+ , Eu 3+ with efficient energy transfer (ET) was synthesized using a high-temperature solid-state reaction. The samples were characterized via X-ray powder diffraction, X-ray photoelectron spectroscopy, photoluminescence spectroscopy, CIE chromaticity coordinates, and fluorescence decay analysis. The energy band and density of states of K 3 Lu(PO 4 ) 2 were analyzed by the first-principles method. The cross-relaxation of Tb 3+ -doped phosphors was investigated as well. The ET from Tb 3+ to Eu 3+ ions, realizing through the electric dipole-dipole (d-d) interaction with a high ET efficiency of 98.36%, could be controlled principally by the Tb 3+ /Eu 3+ doping concentration ratio, yielding the tunable emissions from green (0.293, 0.537) to orange-red (0.563, 0.367) range. Based on the obtained results, a three-phosphor-conversion white light-emitting diode (w-LED) was fabricated through the integration of a 365 nm chip and commercial blue-emitting BaMgAl 10 O 17 : Eu 2+ phosphors, green-emitting SiAlON: Eu 2+ phosphors, and orange-red-emitting K 3 Lu(PO 4 ) 2 : 0.1 Tb 3+ , 0.06Eu 3+ phosphors. The appliance emits the white light at a suitable correlated color temperature of 3678 K and a high color rendering index of 91.4. These parameters are almost equal to those of ideal white light, which opens up the prospects for using this up-and-coming phosphor for warm w-LED applications.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2018
·Vol. 124
·期 3
·1-10
·
IF 1.604
Liu Min,Kang Ming,Chen Kexu,Mou Yongren,Sun Rong
Integrating the processes of preparation of CaCO 3 :Eu 3+ and its surface-coating, core–shell structured CaCO 3 :Eu 3+ @SiO 2 phosphors with red emission were synthesized by the carbonation method and surface precipitation procedure using sodium silicate as silica source. The phase structure, thermal stability, morphology and luminescent property of the as-synthesized samples were characterized by X-ray diffraction, Fourier transform infrared spectrum, thermal analysis, field-emission scanning electron microscopy, transmission electron microscope and photoluminescence spectra. The experimental results show that Eu 3+ ions as the luminescence center are divided into two types: one is at the surface of the CaCO 3 and the other inhabits the site of Ca 2+ . For CaCO 3 :Eu 3+ @SiO 2 phosphors, the SiO 2 layers are continuously coated on the surface of CaCO 3 :Eu 3+ and show a typical core–shell structure. After coated with SiO 2 layer, the luminous intensity and the compatibility with the rubber matrix increase greatly. Additionally, the luminous intensity increases with the increasing of Eu 3+ ions concentration in CaCO 3 core and concentration quenching occurs when Eu 3+ ions concentration exceeds 7.0 mol%, while it is 5.0 mol% for CaCO 3 :Eu 3+ phosphors. Therefore, preparation of CaCO 3 :Eu 3+ @SiO 2 phosphors can not only simplify the experimental process through integrating the preparation of CaCO 3 :Eu 3+ and SiO 2 layer, but also effectively increase the luminous intensities of CaCO 3 :Eu 3+ phosphors. The as-obtained phosphors may have potential applications in the fields of optical materials and functional polymer composite materials, such as plastics and rubbers.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
SOLID STATE SCIENCES
·
2019
·
IF 2.155
Xiaoqing Guo,Shuangju Song,Xue Jiang,Xue Wang,Jiahui Guo,Qingwei Song,Yuanyuan Han,Liyong Wang
Eu 3+ activated CaWO 4 (CWO) phosphors were prepared via a modified hydrothermal process. In present work, the phosphors illustrated enhanced emission properties by the assistance of poly acrylic acid (PAA). The phase structure, micromorphology, photoluminescence properties and luminescence enhancement mechanism of the as-prepared samples were investigated. The as-prepared PAA assisted samples exhibited significantly enhanced red emission peaking at 595 nm and emission intensity increased by about 8 times. The results indicated that CWO: Eu 3+ samples could be a potential candidate of red phosphor for white light-emitting diodes (WLEDs).
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2023
·Vol. 26
·期 6
·835-847
·
IF 3.1
Huimin Du,Jie Yang,Xingzuo Liu,Jun Yang,Shanshan Hu
Monoclinic AgTbW2O8:Eu3+ crystals were prepared by a simple one-step hydrothermal method. The phase, morphology and luminescence properties of the obtained phosphors were systematically characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and photoluminescence (PL). The effects of solution pH, W/Tb molar ratios and reaction temperatures as well as reaction times on the size and morphology of the final products were discussed, and the possible formation mechanism of the almond-like structure was proposed. The down-conversion luminescence properties and energy transfer behavior of the AgTbW2O8:Eu3+ phosphors were studied under ultraviolet light excitation. The emission lights were obtained from green to yellow-green to yellow to red by setting different ratios of Tb3+/Eu3+. The temperature-dependent fluorescence test data showed that AgTbW2O8:Eu3+ phosphors have good temperature stability. In addition, by doping alkali metal ions Li+, Na+, and K+ in AgTbW2O8:Eu3+ phosphors, it is found that the luminescence intensity of phosphors doped with alkali metal ions is enhanced compared with that of phosphors without alkali metal ions, and the phosphor doped with K+ has the largest luminescence intensity, which is due to the introduction of K+ making the crystal field produce the greatest asymmetry.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2021
·Vol. 18
·期 5
·1570-1581
·
IF 1.968
Yangyi Xu,Xiaohui Wang,Yunge Wei,Yuanxi Liu,Guifang Li
CaGd 2 (WO 4 ) 4 :Eu 3+ phosphors with controllable morphology were synthesized via the hydrothermal method. The influences of pH value, reaction time and Eu 3+ concentration on the crystal structure, morphology, and photoluminescence properties of CaGd 2 (WO 4 ) 4 :Eu 3+ were studied. The pure tetragonal structure CaGd 2 (WO 4 ) 4 is obtained when the pH value is 8 and 9. Furthermore, by altering the pH value of the reaction solution, the morphologies of the CaGd 2 (WO 4 ) 4 :Eu 3+ phosphors evolve from spindle-shaped grains to tetragonal plate-like grains and finally to aggregated bulk particles. Under the 394 nm excitation, the phosphors display a bright red emission corresponding to the characteristic 4 f -4 f transitions of Eu 3+ , and the intensity of emission peaks depends mainly on the pH value, the reaction time, and the Eu 3+ concentration. The optimum photoluminescence performance is achieved for CaGd 2- x (WO 4 ) 4 : x Eu 3+ ( x = 1) phosphor synthesized at pH = 8 under the reaction time of 16 h. Finally, the thermal stability of the phosphors is analyzed at different ambient temperatures.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Xin Chen,Qingyu Meng
In this study, CaMoO 4 : Eu 3+ phosphors with molar concentrations of 0.01 %, 0.03 %, and 0.1 % were synthesized via the hydrothermal process. The variable temperature PL spectra demonstrated a pronounced decline in the luminescence of MoO 4 2− with the temperature rising, suggestive of typical thermal quenching behavior, whereas the luminescence of Eu 3+ showcased an emerging trend characterized by an initial increase followed by a decline. This phenomenon was attributed to the intensified energy transfer effect from MoO 4 2− to Eu 3+ as the temperature increased. The thermal quenching trends between MoO 4 2− and Eu 3+ exhibited distinct differences, leading to the acquisition of high relative sensitivity when utilizing the FIR of MoO 4 2− and Eu 3+ for temperature sensing. It was found in the experiment that samples with higher Eu 3+ doping concentrations exhibited higher S r . In the CaMoO 4 : 0.1 % Eu 3+ sample, the S r-max reached 3.19 % K −1 at 303 K, which was an excellent value among inorganic materials. The findings of this paper indicate the potential application of CaMoO 4 : Eu 3+ phosphors for optical thermometry.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2015
·Vol. 50
·期 12
·4405-4411
·
IF 2.371
Yang Jinyu,Jia Xiaohui,Zeng Xiaodao,Zhu Liping,Chen Zhuo
Pure phase of LaP 3 O 9 Eu 3+ phosphors with orthorhombic structure was successfully synthesized by a polyacrylamide gel process. The crystal structure, thermal behavior, and optical properties of the as-synthesized samples were investigated by XRD, TG-DTA, FT-IR, and PL. The effects of some synthesis conditions on the structure and properties of samples were also discussed. The results reveal that the annealing temperature and the ratio of (La+Eu) to P in precursor solutions play a key role in determining the structure and luminescence properties of products. The single-phase orthorhombic structure LaP 3 O 9 :Eu 3+ phosphors can be obtained by annealing at 750–850 °C. The LaP 3 O 9 :Eu 3+ phosphors emit a dominating and intense line at 618 nm, and exhibit improved photoluminescence properties compared with the samples of LaPO 4 :Eu 3+ crystals. The concentration quenching effect can be observed with increasing Eu 3+ concentration over 40 at.%.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2021
·
IF 3.08
Dechuan Li,Gungping Zhu,Xuelian Zhao
KTb(CO 3 ) 2 :Eu 3+ phosphors with intense stokes emission were synthesized by hydrothermal method . Under the excitation of 368 nm light, the pure KTb(CO 3 ) 2 shows an intense green emission at 543 nm corresponding to the 5 D 4 → 7 F 5 transition of Tb 3+ , about 5 times higher than that of the K + -free Tb 2 O(CO 3 ) 2 phosphor. As the Tb 3+ is partly substituted by Eu 3+ , the luminescence color can be transformed from green to red. The intensity of red emission of KTb(CO 3 ) 2 :Eu 3+ could greatly increase as the contents of Eu 3+ without any concentration quenching. Under the excited by 368 nm near-ultraviolet, the quantum efficiencies of KTb(CO 3 ) 2 and KTb(CO 3 ) 2 :0.3Eu 3+ were 93% and 80%, respectively. The high quantum efficiency shows that KTb(CO 3 ) 2 :Eu 3+ is a useful color-tunable luminescence material under excitation of ultraviolet light in the anti-counterfeiting, lighting and display.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2023
·
IF 4.9
Youfa Tai,Ruirui Cui,Jun Zhang,Chunkai Wang,Tingyu Zhao,Beiqiao Zhang,Chaoyong Deng
Novel orange-red Sr 2 GdSbO 6 : x Eu 3+ ( x = 0, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6) phosphors were successfully prepared by the traditional high-temperature solid-state method. The results of Rietveld refinement, energy dispersive spectroscopy (EDS) spectrum and elemental mapping demonstrate that Eu 3+ successfully replaces the Gd 3+ sites and distributes uniformly in the particles of phosphors. The luminescence properties of Sr 2 GdSbO 6 :Eu 3+ phosphors were investigated in detail. The emission spectra of the strongest emission peak is the 5 D 0 → 7 F 1 (593 nm) transition, which can emit orange-red light under 393 nm excitation. When the doping concentration of Eu 3+ ions is x = 0.2, the luminescence intensity of the phosphors reaches the highest. The detailed mechanism of concentration quenching is attributed to dipole-dipole interaction. The thermal stability values of Sr 2 GdSbO 6 :0.2Eu 3+ phosphors are 87%, 82% and 114% under 393, 467 and 527 nm excitations, respectively. The causes of the abnormal thermal quenching under 527 nm excitation were analyzed. Based on the abnormal thermal quenching under 527 nm excitation, the optical thermometry properties of Sr 2 GdSbO 6 :0.2Eu 3+ phosphors were investigated by fluorescence intensity ratio (FIR) technique, and appreciable relative sensitivity was obtained. The results suggest that Sr 2 GdSbO 6 :0.2Eu 3+ phosphors can be potentially applied to w-LEDs and optical thermometers.
研究领域:
材料科学
·
光学
·
磷光材料
·
发光材料
·
光学传感
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）