JOURNAL OF RARE EARTHS
·
2017
·
IF 2.429
Jiansheng Huang,Ronghui Liu,Yuanhong Liu,Yunshen Hu,Guantong Chen,Chunpei Yan,Junhang Tian,Bin Hu
Eu 2+ activated BaSi 2 O 2 N 2 oxynitride bluish-green phosphor was synthesized adopting conventional high-temperature solid-state reaction method, in which BaF 2 , Na 2 CO 3 and NH 4 Cl were used as the fluxes. The phase formation, size distribution and microscopic morphology were characterized to investigate the influence of adding fluxes on photoluminescence properties. The results indicate that with the addition of BaF 2 flux, the particle morphology becomes regular and size distribution narrows and the phase purity of BaSi 2 O 2 N 2 :Eu 2+ phosphor can be improved effectively. The photoluminescence intensity of BaSi 2 O 2 N 2 :Eu 2+ phosphor with BaF 2 as flux gets enhanced obviously, which is much higher than that of Na 2 CO 3 , NH 4 Cl and without flux. The optimum content of BaF 2 flux is 4 wt%, and the maximum photoluminescence intensity of the BaSi 2 O 2 N 2 :Eu 2+ phosphor prepared with BaF 2 flux rises to 141%, meanwhile, the phosphors with BaF 2 flux exhibits low thermal quenching. The results indicate that the BaSi 2 O 2 N 2 :Eu 2+ is sort of promising bluish-green phosphor for application in full-spectra LED.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Frontiers in Materials
·
2025
·
IF 2.9
Liwu Fu,Jiangfeng Hu,Peng Luo,Dong Xiang,Wenying Hui,Lei Cheng,Yan Zhou,Xiong Zhengrong,Dengzun Yao,Xianghai Jing
The white weathering layer materials that can effectively block the entire solar light band is of great importance for improving the service life, safety, and reliability of the materials. In this work, CsxWO3@PDA was prepared by in situ polymerization to achieve high absorption in the full spectral range and increase the compatibility between CsxWO3 particles and polyvinylidene fluoride (PVDF). PVDF composite films with different particle contents were prepared through compounding with titanium dioxide (TiO2) and CsxWO3@PDA. The prepared composite films were characterized by FT-IR, field emission scanning electron microscopy, universal material testing machine, whiteness meter, and ultraviolet visible spectroscopy. The results showed that the CsPVDF composite films with CsxWO3@PDA and TiO2 exhibited a whiteness level higher than 74, a transmittance of less than 5% in the wavelength range of 200–2500 nm, and a transmittance close to zero in the range below 1750 nm, demonstrating excellent shielding effect. The xenon lamp aging test also confirmed that the composite films had excellent weather resistance after aging 500 h. At the same time, adding a certain amount of CsxWO3@PDA could improve the tensile strength of PVDF.
研究领域:
材料科学
·
聚合物工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Optical Materials
·
2021
·Vol. 9
·期 19
·2100337
·
IF 9.926
Dan Zhang,Xiangting Zhang,Baofeng Zheng,Qi Sun,Zhibo Zheng,Zhan Shi,Yanhua Song,Haifeng Zou
A series of Eu 2+ single doped Ca 9 Na 1– x Li x Sc 0.667 (PO 4 ) 7 phosphors with full-spectrum emission have been synthesized. Under the 385 nm excitation, the Eu 2+ single doped Ca 9 NaSc 0.667 (PO 4 ) 7 without Li + doping displays a broad cold white light emission with the peaks at about 480 and 610 nm. With the introduction of Li + ions, the Eu 2+ ions selectively occupy the Ca1, Ca2/Ca3, and Na sites. The variation of local environment of Eu 2+ ions caused by Li + ions enhances the luminous intensity, solves the problem of the lack of a red light component, and realizes the emission color tuning from cold white via warm white to orange. A special charge compensation method caused by Li + migration avoids the generation of defects and is beneficial to the improvement of luminescence properties. Eventually, a warm white light-emitting diode device is prepared by combining the white emitting Ca 9 Na 0.8 Li 0.2 Sc 0.667 (PO 4 ) 7 :2%Eu 2+ phosphors with 385 nm LED chip, which exhibits a high color-rendering of 92.9, low correlated color temperatures of 4529 K, and excellent color stability under working temperature. The as-reported warm white emitting Eu 2+ -doped phosphors have potential applications in full-spectrum solid-state lighting. The site engineering strategy provides an extensive guide for optimizing and designing novel single-composition white-emitting phosphor materials.
研究领域:
材料科学
·
光学工程
·
固态照明
✓ 已验证
DOI
高影响因子
Materials Today Physics
·
2024
·
IF 10
Daiyuan Liu,Ru Zhao,Chao Wang,Zhichao Liu,Jian Zhang,Yuan Wang,Xue Yu,Jianbei Qiu,Xuhui Xu,Yichun Liu
High-quality phosphors with color tunability are urgently needed for the full-spectrum white light-emitting diodes (WLEDs) with healthy and comfortable lighting like the solar spectrum. Here, a Sr 2 Ga 2 SiO 7 : Eu 2+ phosphor with tunable luminescence color is reported, achieving a luminescence tuning from maize-yellow to yellow by changing the Eu 2+ ion concentration. Importantly, the quantum efficiency of BaSrGa 2 SiO 7 : 1.0 % Eu 2+ is as high as 85.7 % compared with 49.1 % of Sr 2 Ga 2 SiO 7 : 5.0%Eu 2+ , and the emission intensity of BaSrGa 2 SiO 7 : 1.0 % Eu 2+ retains 92 % of the room temperature (RT) emission intensity at 473 K by Ba 2+ substitution. Furthermore, the increase of Ba 2+ ion concentration also makes the phosphor achieve tunability from yellow to green. The as-prepared full-spectrum WLEDs exhibits a continuity spectrum like solar spectrum with an extremely high color rendering index of 93.5 and low correlated color temperature of 4562 K. This work provides new insights into the exploration of new phosphors for high-performance full-spectrum WLEDs devices.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2023
·
IF 3.8
Gaoliang Wang,Jian Li,Liuyang Xu,Honglei Yuan,Xianke Sun
Bi 3+ activated phosphors show potential applications in white light emitting diodes. Here, Bi 3+ activated SrBaGdGaO 5 phosphors with different Bi 3+ concentrations were prepared. The phase and oxidation states, absorbance/excitation/emission spectra, decay characteristics, and thermostability were researched. Depending on excitation of NUV light, the Bi 3+ activated SrBaGdGaO 5 phosphors emit cyan light originating from the radiative 3 P 1 → 1 S 0 transitions of Bi 3+ . On the basis of temperature-dependence emission spectra, the activation energy was calculated as 0.305 eV. The warm white light with a correlated color temperature of 4106 K and a color rendering index of 89.2 was emitted by the WLED device consisting of near ultraviolet LED chips, SrBaGdGaO 5 :Bi 3+ and CaAlSiN 3 :Eu 2+ phosphors. The luminescence performance of the cyan SrBaGdGaO 5 :Bi 3+ phosphors indicates that they can remedy the cyan absence for full spectrum white lighting emitting diodes.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2015
·Vol. 8
·期 11
·3621-3629
·
IF 7.01
Li Yanrui,Li Leilei,Gong Yunqi,Bai Song,Ju Huanxin,Wang Chengming,Xu Qian,Zhu Junfa,Jiang Jun,Xiong Yujie
A Z-scheme is a promising approach to achieve broad-spectrum photocatalysis. Integration of TiO 2 with another semiconductor with a band gap of ∼1.0 eV would be ideal to harvest both ultraviolet and visible-near infrared light for photocatalysis; however, most narrow-bandgap semiconductors have straddling band structure alignments with TiO 2 , constituting an obstacle to forming the Z-scheme for photocatalytic hydrogen production. In this communication, we demonstrate Ag 2 S as a model system where the energy band upshift of the narrow-bandgap semiconductor that shares an interface with a metal can overcome this limitation. To fabricate the design, we developed a unique approach to synthesize Ag 2 S–Ag–TiO 2 hybrid structures. The obtained ternary hybrid structures exhibited dramatically enhanced performance in photocatalytic hydrogen production under full-spectrum light illumination. The activities were significantly higher than the sum of those of Ag 2 S–Ag–TiO 2 structures under λ < 400 nm and λ > 400 nm irradiation as well as those of their counterparts under any light illumination conditions.
研究领域:
材料科学
·
能源化学
·
环境科学
✓ 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
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Qinghai Sun,Zhibo Zheng,Xiaolu Yang,Yanxia Zhao,Zhou Luo,Chao Wang,Yanhua Song,Haifeng Zou,Shihou Sheng
Herein, a variety of single-phase full-spectrum emission phosphors doped with Eu 2+ were synthesized. Under the 350 nm excitation, as K + and Y 3+ were introduced into Ca 10 Na(PO 4 ) 7 (CNP):1.5%Eu 2+ , respectively, the emission color of Ca 9.85 K y Na (1- y ) ( PO 4 ) 7 :1.5%Eu 2+ (0 ≤ y ≤ 1.0) was tuned from yellow to cyan, while that of Ca (9.85- z ) NaY 0.667 z (PO 4 ) 7 :1.5%Eu 2+ (0 ≤ z ≤ 1.0) was tuned from yellow to green. The internal quantum yield (QY) of Ca 9·85 K 0·4 Na 0·6 (PO 4 ) 7 (CKNP):1.5%Eu 2+ and Ca 9·45 NaY 0·267 (PO 4 ) 7 (CNYP):1.5%Eu 2+ reached 47.47 % and 27.11 %, respectively. The introduction of K + or Y 3+ made Eu 2+ selectively occupy the Ca sites and led to changes in the local environment of Eu 2+ , allowing for spectral tuning emission. In addition, the luminescence intensity of the samples retained 54.59 % and 31.34 % of their room temperature values. Eventually, two white light emitting diode (WLED) devices were fabricated, combining the synthesized white emitting phosphors with 365 nm ultraviolet (UV) chips. They exhibited high color rendering indices of 84.7 and 77.0, along with low correlated color temperatures of 5435 K and 5023 K. The Commission Internationale de L'Eclairage (CIE) color coordinates were (0.3349, 0.3975) and (0.3517, 0.4366), respectively. The results pointed to the phosphors' potential suitability for use in the WLED sector.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
·
IF 5.8
Zongliang Xiao,Weizhen Liu,Gan Wan,Jianlei Liu,Lu Yu,Qian Zhang,Lei Han
The quest for advanced full-spectrum lighting technologies has driven the development of W-LEDs, while challenges remain in finding effective cyan emitters and ensuring outstanding thermostability. This study detailed the synthesis of the europium-doped CaO-Al 2 O 3 -SiO 2 -YF 3 glass-ceramics (GCs), which demonstrated efficient cyan emission when irradiated by 419 nm light, with a spectacular internal quantum efficiency of up to 83.24 %, and outstanding thermal stability of 90.2 %@100℃ compared to room temperature intensity. In practical applications, this GC was integrated with a 420 nm LED chip, (Sr, Ca)AlSiN 3 : Eu 2+ red and Y 3 Al 5 O 12 : Ce 3+ yellow phosphor in a prototype full-spectrum W-LED device. The device achieved an excellent color rendering index (94), appropriate chromaticity coordinates (0.3789, 0.3950), and a well-defined correlated color temperature (4163 K). This study not only advances the application of GCs within W-LED technology but also reveals their potential in driving energy-saving and eco-friendly lighting solutions, thus providing a path to achieve superior full-spectrum lighting technology.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Lei Fu,Di Wu,Yanfei Xiao,Wanfang Zou,Jinfen Kuang,Yan Liang,Fu Du,Jiaqing Peng,Xinyu Ye
Blue phosphor Sr 5−x-y R y (PO 4 ) 3 Cl:xEu 2+ (R = La, Gd, Lu) was prepared via solid-state reaction process, in which R 3+ replaces part of Sr 2+ ions in the matrix to benefit Eu 2+ luminescence. The change of Eu 2+ /Eu 3+ values were studied by XPS , and the results shown that the incorporation of R 3+ in the matrix resulted in the values increase of Eu 2+ /Eu 3+ . And substitute R 3+ non-equivalently for Sr 2+ , the modified Sr 5−x-y R y (PO 4 ) 3 Cl:xEu 2+ phosphors show better luminescence intensity and thermal stability. The emission intensity of Sr 4.72 Lu 0.2 (PO 4 ) 3 Cl:0.08Eu 2+ is 1.97 times of Sr 4.95 (PO 4 ) 3 Cl:0.05Eu 2+ . Moreover, the thermal quenching of Eu 2+ photoluminescence could be reduced. Compared to the commercial BAM:Eu 2+ phosphor, the stabilities of all Sr 4.72 R 0.2 (PO 4 ) 3 Cl:0.08Eu 2+ (R=La 3+ , Gd 3+ and Lu 3+ ) phosphors are better than that of BAM:Eu 2+ at the temperatures below 100 °C. The luminescent intensity of Sr 4.72 Lu 0.2 (PO 4 ) 3 Cl:0.08Eu 2+ maintains 95% while BAM:Eu 2+ is only 88% of the initial intensity at 150 °C. By combining Sr 4.72 Lu 0.2 (PO 4 ) 3 Cl:0.08Eu 2+ , Y 3 (Al,Ga) 5 O 12 :Ce 3+ and CaAlSiN 3 :Eu 2+ with 400 nm near-ultraviolet LED chip, a white-light-emitting diode was obtained. The fabricated WLED device with CIE color coordinates x = 0.3896, y = 0.3788, low CCT (3775 K) and high Ra (95.1), has enormous potential application in full-spectrum lighting field.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Jinzhu Wu,Yue Liu,Yuan Yao,Yanbin Shao,Xiaohong Wu
Superabsorbers can find application in the fields of solar cells, blackbody radiation, thermal control systems, and stray light elimination devices. Herein, graphene-like 2H/1T-molybdenum diselenide (MoSe 2 ) was synthesized via a hydrothermal method and shows superhigh solar absorption (~99%) within a range of 200–2500 nm. In the synthesis, selenium dioxide (SeO 2 ) was used as a Se source instead of Se powder, which plays an important role in manipulating the graphene-like morphology and the multiphasic composition of the MoSe 2 . Consequently, the as-prepared MoSe 2 nanoflowers possess desired band structure and abundant pores and pore channels for strong optical absorption. DFT calculations clarify that the 1T-MoSe 2 primarily contributes to the superior optical absorption over the 2H-MoSe 2 . This work provides a facile strategy for enhancing the optical absorption of two-dimensional transition metal dichalcogenides (2D TMDCs) by engineering morphology and phase.
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2020
·Vol. 31
·期 8
·2007591
·
IF 16.836
Hanlin Huang,Cong Wang,Qi Li,Ruiqi Wang,Yuying Yang,Aidaer Muhetaer,Fuqiang Huang,Bing Han,Dongsheng Xu
Efficient hydrogen release from ammonia borane (AB) with a striking hydrogen content (19.6 wt%) via thermolysis provides a promising pathway for on-board applications utilizing hydrogen energy. However, the sluggish kinetics at low temperatures and high energy consumption of thermal dehydrogenation are major obstacles for hydrogen release from AB. Herein, a novel solar-driven strategy for hydrogen production from AB at low temperature is proposed, in which Ti 2 O 3 is utilized as a full-spectrum light absorber for photothermal-activating solid-state AB reactants to produce hydrogen. Through a reduction transformation method, nanoscale Ti 2 O 3 particles with high chemical stability and narrow band gap are prepared, realizing a rapid production of 2.0 equivalents of hydrogen from AB at ambient temperature, with an excellent recyclable and full-spectrum-responsive photothermal dehydrogenation. Importantly, a record high photothermal activation efficiency of 35% is achieved with nanoscale Ti 2 O 3 particles due to an enhanced local photothermal effect contributed by improved light absorption and decreased thermal conduction. Moreover, assisted with CuCl 2 promoter, a release of 2.0 equivalents of hydrogen under 1.0 solar irradiation at 70 °C is successfully achieved, revealing its potential applications in practical vehicles based on proton exchange membrane fuel cells.
研究领域:
材料科学
·
能源化学
✓ 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）