CERAMICS INTERNATIONAL
·
2022
·Vol. 49
·期 7
·10273-10279
·
IF 5.532
Daiyuan Liu,Ting Wang,Yichun Liu,Chao Wang,Zhichao Liu,Xiaodie Zhu,Ya Liu,Jian Zhang,Zhaowei Teng,Yang Zhong,Yakovlev Alexey Nikolaevich,Xuhui Xu
The photoluminescence behavior of inorganic phosphors is generally influenced by thermal stability, which determines the luminescence efficiency of the corresponding devices. Here, a series of Eu 2+ , Mn 2+ co-doped LiAl 5 O 8 blue-green-emitting phosphors with thermal robust are successfully fabricated. The concentration-dependent emission spectra and the decay curves of the as-obtained LiAl 5 O 8 : Eu 2+ , Mn 2+ samples manifest the occurrence of the energy transfer from Eu 2+ to Mn 2+ ions via dipole-dipole interaction, and the corresponding emitted colors are gradually modulated from blue to green under the excitation of 310 nm. Moreover, the zero-thermal-quenching luminescence is observed when the operation temperature is up to 423 K, which is attributed to the energy release from the trapping centers to emitting centers (Eu 2+ and Mn 2+ ) at high temperature. Furthermore, a warm white light-emitting diodes (WLEDs) device with correlated color temperature of 5061 K, a color rendering index of 80.6 and long-term stability is fabricated by combining UV LED chip (λ ex = 310 nm), as-obtained LiAl 5 O 8 : Eu 2+ , Mn 2+ phosphor, commercially available red phosphor and green phosphor. These results prove the potential application of the as-obtained LiAl 5 O 8 : Eu 2+ , Mn 2+ phosphor for UV-pumped WLEDs devices.
研究领域:
材料科学
·
发光材料
·
固态化学
·
光电子学
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无机化学
·
器件物理
·
纳米材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Simin Gu,Mao Xia,Cheng Zhou,Zihui Kong,Maxim S. Molokeev,Li Liu,Wai-Yeung Wong,Zhi Zhou
The discovery of novel Mn 4+ -doped oxide red phosphor with suitable spectrum for plant growth is a hot issue in the recent years due to the characteristic red photoluminescence of 2 E g → 4 A 2 transition in Mn 4+ ions. Generally, the emission position of Mn 4+ is hard to tune because of specific crystal field in most phosphors. In this work, tunable luminescence property with obvious red shift in the spectra is observed in the Mn 4+ -doped SrMgAl 10-y Ga y O 17 red phosphor via simple substitution of Ga 3+ for Al 3+ , and crystal field theory and nephelauxetic effect are employed to explain this phenomenon. Meanwhile, the Ga 3+ dopant changes the shape of the spectra because Ga 3+ dopant guides the replacement site of Mn 4+ and changes the luminescence center. Improved emission intensity is obtained because appropriate Ga 3+ doping leads to larger band gap and reduces non-radiative transitions. Phosphor-converted LED (pc-LED) devices fabricated with blue chip (470 nm) and the as-obtained SrMgAl 10-y Ga y O 17 :1.0%Mn 4+ phosphors emit bright blue and red light, which fit the absorption regions of plant pigments well, thus SrMgAl 10-y Ga y O 17 :Mn 4+ phosphor can be a candidate for plant growth LED light.
研究领域:
材料科学
·
光电子学
·
固体化学
·
农业光生物学
·
发光材料
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2023
·
IF 3.9
Jiajie Pan,Youjie Hua,Zhanhao Fan,Hongping Ma
Far-red light plays a crucial role in the field of plant lighting. Herein, a novel far-red phosphor BaAl 2 Si 3 O 4 N 4 : Sm 2+ , which can be effectively excited by blue light, was successfully prepared by high-temperature solid-state reaction. The PL spectrum show a broadband emission range from 600 nm to 950 nm (FWHM = 120 nm), which is well matched with the absorption of P FR in plant. In BaAl 2 Si 3 O 4 N 4 : Sm 2+ , the Ba 2+ are coordinated with three N and six O atoms. When the rare earth ion of Sm 2+ was doped into the host lattice , Ba 2+ was partially replaced by Sm 2+ . The low temperature PL spectra at 8–80 K were studied in detail. It was found that the PL spectra at low temperature were composed of some sharp lines and broadband superposition, which corresponding to the 5 D 0 - 7 F J (J = 0–4) energy level transition of Sm 2+ . It is shown that the broadband emission of the phosphor was caused by the broadening of the 4f 5 5 d 1 energy level due to the strong crystal field effect. The thermal stability analysis showed that the luminescence intensity of BaAl 2 Si 3 O 4 N 4 : Sm 2+ at 150 °C still maintains 62.7 % of that at room temperature , showing excellent thermal stability. All results indicate that BaAl 2 Si 3 O 4 N 4 : Sm 2+ phosphor has important potential applications in the field of plant lighting.
研究领域:
材料科学
·
光电子学
·
农业光学
·
无机化学
·
发光材料
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2020
·
IF 3.28
Zhiqin Zheng,Peizhang Xie,Panpan Yi,Jun Zhao,Lihong Liu,Facheng Yi
Nowadays, ultraviolet (UV) and blue converted phosphors have played a key role in the solid-state lighting field, and the white light is usually produced by mixing multiple phosphors. In this work, we report a type of UV converted single white phosphor, i.e. , Ba 9 La 2 Si 6 O 24 :Eu 3+ ,Bi 3+ .Various techniques, such as powder X-ray diffraction (XRD), scanning electron microscopic (SEM), photoluminescence (PL) spectra, and quantum efficiency (QE), have been used to characterize the samples. In Bi 3+ doped samples, upon excitation within the wavelength range of 250–380 nm can lead to three Bi 3+ emission bands ( i.e. , 358 nm, 415 nm, and 516 nm), but only one emission band peaking at 415 nm appears when the excitation wavelength exceeds 380 nm. Structural analysis and discussion on the PL intensity variation reveal there are three Bi 3+ luminescent centers at two different La 3+ sites and one Ba 2+ site. The Bi 3+ concentration-induced luminescent quenching is dominated by the d-d interaction. In view of the spectral overlap between the Bi 3+ emissions and the Eu 3+ excitation spectra , the energy transfer from Bi 3+ to Eu 3+ of the Ba 9 La 2 Si 6 O 24 :Eu 3+ ,Bi 3+ is studied, and it is dominated by a dipole-quadrupole ( d - q ) interaction. Moreover, upon excitation at 365 nm, the emissions broadly tuning from blue, white and to red are achieved by varying the Eu 3+ content. For the white Ba 9 La 2 Si 6 O 24 :Eu 3+ ,Bi 3+ sample, high temperature PL results show that it does not have severe degradation of emission intensity after increasing the temperature from 25 to 300 °C, exhibiting a good thermal stability . To show the potential application in the lighting fields, we fabricate a white light LEDs device by depositing this white phosphor on a 365 nm UV LED chip. As a result, the values, i.e. , a color rendering index (CRI) of 95, luminous efficiency of 80 lm/W, and color temperature (CT) of ~4215 K at chromaticity (0.382, 0.398), are achieved.
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
CERAMICS INTERNATIONAL
·
2023
·Vol. 50
·期 6
·9753-9761
·
IF 5.2
Li Li,Haoliang Yang,Yongjie Wang,Faling Ling,Xianju Zhou,Guotao Xiang,Zhongmin Cao,Sha Jiang,Zhiyu Yang,Yongbin Hua
Novel Ca 2 ScNbO 6 (CSNO): Cr 3+ phosphors were synthesized through a solid-phase method. The crystal structures, luminescence performances, and applications were introduced in this work. The optimized doping concentration was found with a Cr 3+ concentration of 0.01 mol. Under the 336 nm excitation, the recorded photoluminescence spectrum in the range of 650–1300 nm indicated that the obtained sample can emit a broad near-infrared emission with a dominant peak of 858 nm while the full width at half maximum (FWHM) was determined to be 191 nm. To gain a deeper comprehension of the luminescent properties, the crystal field strength was investigated as Dq/B = 2.03, and the electron-phonon coupling for parameter S was calculated to be about 2.01. As for the potential application, utilizing the variable temperature decay lifetime technique, the relative sensitivity (S R ) was approximately 1.16% K −1 at 387 K, which can be promised for utilization in optical temperature measurement. On the other hand, a near-infrared phosphor-converted lighting-emitting diode ( Pc -LED) was fabricated for night vision. Eventually, the security ink based on the obtained sample was made for use in the anti-counterfeiting field.
研究领域:
材料科学
·
光学工程
·
无机化学
·
功能材料
·
生物医学工程
✓ 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
Laser & Photonics Reviews
·
2023
·Vol. 18
·期 1
·2300732
·
IF 11
Zhuowei Li,Ge Zhu,Shanshan Li,Wen Xu,Qingfeng Bian,Yan Cong,Ming He,Xixian Luo,Shuangyu Xin,Bin Dong
The burgeoning phosphor-converted near-infrared light-emitting diodes (pc-NIR LEDs) have important applications in special illumination and spectroscopy analysis. However, the development of efficient NIR-emitting phosphors with high performance is still a challenge. In this work, a chemical unit co-substitution strategy is proposed to realize the excitation transition regulation and successfully achieve high-performance NIR luminescence in Ca 3- y Na y Mg 1- y Sb 2- x Al 2+ y O 12 : x Cr 3+ (0 ≤ x ≤ 0.05, 0 ≤ y ≤ 1) garnet-type solid solution phosphors. Through the excitation transition modulation from the 4 A 2 ground state to the 4 T 1 ( 4 P) and 4 T 1 ( 4 F) excitation state, the excitation intensity at the blue light region is largely enhanced by 25.6 times. Moreover, the NIR-emitting efficiency and thermal stability are improved, with the optimal luminescence internal quantum efficiency of 90.6% and thermal stability of 97%@423 K, without any flux-assisted sintering or reduction atmosphere protection. The structure regulation induced small Stokes shift, weak electron-phonon coupling effect, and decreased non-radiative transition are responsible for the excellent NIR-emitting performance. Finally, the NIR pc-LED is fabricated with photoelectric efficiencies of 18.7%@100 mA and NIR output powers of 63 mW@100 mA, presenting potential applications in nondestructive internal defect detection, veins imaging, and night vision surveillance.
研究领域:
材料科学
·
光学工程
·
固体化学
·
发光材料
·
半导体器件
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·Vol. 46
·期 13
·21560-21568
·
IF 3.83
Mingcai Li,Xuejie Zhang,Yinjian Zheng,Yaliang Xu,Haoran Zhang,Yingliang Liu,Bingfu Lei
The discovery of light converter excited by near-ultraviolet (UV) superior broadband blue-emitting lighting source is a main challenge in plant growth LEDs. In this study, SrLu 2 O 4 :Ce 3+ , Li + , F − blue phosphor has been synthesized via a solid-state reaction. Benefitting from doping of F − ions, SrLu 2 O 4 :Ce 3+ , Li + , F − phosphor (λ ex = 405 nm, λ em = 460 nm) shows a strong broadband (FWHM = 90 nm) blue-emitting with lower critical concentration of Ce 3+ ions and an increasing 6.9% thermal quenching performance (92.1% @ 423 K of the peak intensity at room temperature). Moreover, a blue light converter composed of SrLu 2 O 4 :Ce 3+ , Li + , F − phosphor and glass matrix is obtained based on phosphor-in-glass (PiG) technology, exhibiting excellent thermal stability and outstanding moisture resistance . A red light converter with commercial red phosphor is obtained by the same method. Furthermore, by combining of two light converters with near-UV chip, a proof-of-concept plant growth high power LED is achieved and applied in indoor Italian lettuce growing in comparison with commercial plant lamps.
研究领域:
材料科学
·
光学工程
·
农业光电子学
·
固体发光
·
无机非金属材料
✓ 已验证
DOI
高影响因子
Laser & Photonics Reviews
·
2024
·Vol. 18
·期 11
·2400447
·
IF 9.8
Fangyi Zhao,Yuhe Shao,Quanlin Liu,Jiasong Zhong
Near-infrared (NIR) phosphor-converted light-emitting diode (pc-LED) light sources in the second NIR window (NIR-II, 1000–1700 nm) have sparked great interest for their emerging applications in non-destructive detection and medical diagnostics fields. However, the development of efficient NIR-II phosphors that can be excited by commercial blue LED chips remains a significant challenge, and thus impeding the applications of NIR pc-LED. Herein, a blue-light-excitable broadband NIR-II luminescence of Ni 2+ is achieved upon incorporating Cr 3+ and Ni 2+ into the Ca 3 Ga 2 Ge 3 O 12 (CGGO) host simultaneously. Through the energy transfer from Cr 3+ to Ni 2+ , CGGO:Cr 3+ ,Ni 2+ phosphor presents the improved NIR-II emission peaking at 1470 nm under 460 nm blue light excitation. The internal/external quantum efficiency values are significantly improved from 13.8%/3.3% to 24.6%/13.3% along with the enhanced luminescence thermal stability. Finally, a NIR pc-LED is fabricated by combining CGGO:Cr 3+ ,Ni 2+ phosphor with 450 nm blue chip, and its potential applications in non-destructive examination and biomedical imaging fields have been demonstrated. The strategy of Cr 3+ and Ni 2+ co-doping solves the problem that Ni 2+ luminescence cannot be effectively excited by blue light and provides the design insights to exploit more ultra-broadband NIR pc-LEDs based on blue LED chips.
研究领域:
材料科学
·
生物医学工程
·
光学成像
·
非侵入性检测
·
分子影像学
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2015
·
IF 2.288
Zhiyong Mao,Jingjing Chen,Liang Sun,Qifei Lu,Dajian Wang
(Ba,Sr) 3 MgSi 2 O 8 :Eu 2+ , Mn 2+ phosphors with 430/505/660 nm tri-bands or 430/660 nm dual-bands emission were demonstrated in this work by controlling the appearence or not of green emitting intermediate phases, (Ba,Sr) 2 SiO 4 :Eu 2+ . Through varying the stoichiometric amount of SiO 2 in precursor, the coexistence of green emitting intermediate phase tended to be sensitive and diversified. Laser Microzone Raman spectrum was employed to look insight into the lattice stretch and the preferential occupation sites of Ba 2+ ions in Sr 3 MgSi 2 O 8 lattices. The local structure and the crystal field of Eu 2+ luminescent centers were found to be disturbed by distorted arrangement of cross-linked [MgO 6 ] octahedra and [SiO 4 ] tetrahedra. This mechanism approach provided some new insights to further understanding the adjustment strategy of green emitting intermediate phases in (Ba,Sr) 3 MgSi 2 O 8 :Eu 2+ , Mn 2+ phosphor potentially applied as red/blue dual-bands emitting or red/green/blue tri-bands emitting materials.
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 LUMINESCENCE
·
2022
·
IF 4.171
Lin Xiang,Xianju Zhou,Yongjie Wang,Li Li,Sha Jiang,Guotao Xiang,Chuan Jing,Jingfang Li,Lu Yao
Near infrared (NIR) light emitting phosphors have attracted more and more attention with the development of science and technology . Herein, we report a series of environmentally-friendly low-cost Fe 3+ -activated ZnGa 2 O 4 phosphors which exhibit intense broadband NIR light emitting. According to density functional theory (DFT) calculations, ZnGa 2 O 4 host possesses an indirect wide bandgap. The emission of the Fe 3+ -doped phosphors demonstrates a wide band spanning from 650 to 850 nm, with the maximum at 720 nm and a full width at half maxima (FWHM) of 70 nm, showing a large overlap with the absorption of phytochromes (PR and PFR). The luminescence intensity remains at 71% when the temperature is raised to 423 K. The phosphors are fabricated into light emitting diodes (LEDs) which produces strong NIR emission with CIE color coordinates of (0.65, 0.31). All these results suggest that ZnGa 2 O 4 :Fe 3+ is a promising NIR luminescent material , which is expected to be a candidate for indoor plant culture LEDs.
研究领域:
材料科学
·
光电子学
·
农业生物技术
·
固体物理
·
无机化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）