OPTIK
·
2017
·
IF 0.835
Renping Cao,Jijun Huang,Xiangfeng Ceng,Zuofu Hu,Ting Chen,Wen Hu,Xinqin Zhang
Ca 3 Nb 2 O 8 :Sm 3+ phosphor is synthesized by solid-state reaction method in air. Host Ca 3 Nb 2 O 8 emits blue light with excitation 260 and 314 nm, and its emission band peaking at ∼460 nm is attributed to the 3 T 1,2 → 1 A 1 transations in [Nb 2 O 8 6− ] group. Ca 3 Nb 2 O 8 :Sm 3+ phosphor with excitation 314 nm shows a systematically tunable emission by adjusting Sm 3+ ion concentration , and only emits reddish-orange light with excitation 407 nm. Excitation band indicates that Ca 3 Nb 2 O 8 :Sm 3+ phosphor may be effectively excited by (∼407 nm) near ultraviolet light-emitting diode chip. The optimal Sm 3+ ion concentration is ∼5 mol% in Ca 3 Nb 2 O 8 :Sm 3+ phosphor. Emission intensity of Ca 3 Nb 2 O 8 :Sm 3+ phosphor may be increased ∼1.4 times by co-doping Li + ions as charge compensator and fluxing agent roles. The experimental results will contribute to studying novel Sm 3+ -doped luminescent materials.
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 Physical Chemistry C
·
2017
·
IF 4.536
Yiru Zhu,Shuwen Zhao,Bin Zhou,Hao Zhu,Youfa Wang
In this work, we report a phenomenon that upconversion emission intensity of Er3+ was enhanced by cadmium. Cd2+ was taken with 0, 3, 10, 20, 30, and 40 mol % as a new dopant to codope LiY0.78Yb0.20Er0.02F4, meanwhile the doping effects on the crystal structure, morphology, and upconversion fluorescence emission are investigated by XRD, Rietveld refinement, TEM, and upconversion spectroscopy analysis methods in detail. The green upconversion emission intensity was enhanced, and the maximum emission intensities were enhanced to twice when 10 mol % Cd2+ was codoped into tetragonal LiYF4, while its decay lifetime was reduced. Additionally, we further designed the synthesis of the homogeneous LiYF4:20%Yb,2%Er,10%Cd@LiYF4 of which the emission intensity is 11 times higher than that of the Cd2+-free nanocrystals, meanwhile an intriguing morphology of core–shell nanocrystals was obtained. This investigation may be useful for the design and improvement of upconversion materials for fulfilling the prerequisite of the practical application.
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 ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Yanzhen Yin,Wenhua Yang,Zhen Wang,Yue Zhang,Maochen Zhu,Chao Dou,Yang Che,Shijia Sun,Chen Hu,Bing Teng,Jiaqi Zhao,Jingyao Lu,Ruyi Sun,Degao Zhong
The struggle with "thermal load" is always an unavoidable challenge for photo-luminescent material. In this work, a novel red phosphor of ZnGa 2 O 4 : Eu 3+ with spinel-type structure is prepared by high-temperature solid-phase method. Due to the charge imbalance during the replacement processes of Ga 3+ →Zn 2+ and Eu 3+ →Zn 2+ in mixed spinel structure, vacancy defects can be introduced into the lattice structure of ZnGa 2 O 4 : 0.02Eu 3+ . The results of Density Function Theory (DFT) calculation demonstrate that the existence of vacancy defects can construct defect energy levels in the energy band structure of the host crystal, which can assist enhancing the fluorescence emission intensity of the phosphor at high temperature. The strong thermal stability of its own structure combined with the assistance of defect energy levels enables the achievement of zero-thermal quenching in ZnGa 2 O 4 : 0.02Eu 3+ under multi-wavelength excitation. Our results open up a new way for the exploration and utilization of zero-thermal quenching phosphors.
研究领域:
材料科学
·
发光材料
·
固态化学
·
计算材料学
·
无机功能材料
✓ 已验证
DOI
高影响因子
Nature Communications
·
2023
·Vol. 14
·期 1
·1-12
·
IF 16.6
Zhong Yuan,Zhang Jiangwei,Li Tingting,Xu Wenwu,Yao Qiaofeng,Lu Min,Bai Xue,Wu Zhennan,Xie Jianping,Zhang Yu
The restriction of structural vibration has assumed great importance in attaining bright emission of luminescent metal nanoclusters (NCs), where tremendous efforts are devoted to manipulating the surface landscape yet remain challenges for modulation of the structural vibration of the metal kernel. Here, we report efficient suppression of kernel vibration achieving enhancement in emission intensity, by rigidifying the surface of metal NCs and propagating as-developed strains into the metal core. Specifically, a layer-by-layer triple-ligands surface engineering is deployed to allow the solution-phase Au NCs with strong metal core-dictated fluorescence, up to the high absolute quantum yields of 90.3 ± 3.5%. The as-rigidified surface imposed by synergistic supramolecular interactions greatly influences the low-frequency acoustic vibration of the metal kernel, resulting in a subtle change in vibration frequency but a reduction in amplitude of oscillation. This scenario therewith impedes the non-radiative relaxation of electron dynamics, rendering the Au NCs with strong emission. The presented study exemplifies the linkage between surface chemistry and core-state emission of metal NCs, and proposes a strategy for brighter emitting metal NCs by regulating their interior metal core-involved motion.
研究领域:
材料科学
·
纳米技术
·
光学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanophotonics
·
2017
·Vol. 7
·期 2
·473-478
·
IF 4.492
Lihua Ye,Fangjie Li,Changgui Lu,Zhixiang Cheng,Guohua Hu,Yanqing Lu,Yiping Cui
The random laser from sheared dye-doped polymer-dispersed liquid crystal (DDPDLC) is investigated. As the emission intensity weakens, the threshold of random laser from DDPDLC increases from 2.0 mJ/pulse to 4.0 mJ/pulse, and the degree of polarization (DOP) increases from 0.1 to 0.78, obviously when the shear distance increases from 0 mm to 4 mm. As the liquid crystal droplets are gradually oriented in the shear direction caused by alignment direction of polymer chain and anisotropy of droplet shape, the scattering intensity perpendicular to the shear direction gradually decreases and that parallel to the shear direction gradually increases. The anisotropic absorption of the laser dye also plays a certain role as the shear distance is 0 mm. The controllable intensity and polarization degree of random laser have a huge potential for sensing applications.
研究领域:
光学
·
材料科学
·
光子学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY AND BUILDINGS
·
2015
·
IF 2.884
Zhijian Liu,Wenlu Xu,Anni Lin,Tao He,Fan Lin
NaGd(WO 4 ) 2 :Eu 3+ /Bi 3+ films were deposited on SiO 2 glass substrates by spin-coating. The as-prepared films were heat treated at different temperatures. The properties of films were characterized by TG-DSC, XRD, SEM and fluorescence spectrophotometer. The TG-DSC curve indicated that films began to crystallize at about 600 °C. The XRD patterns and SEM images of films annealed at 600 °C, 700 °C and 800 °C showed that a higher temperature benefits to the higher crystallinity and induces the lower thickness. Meanwhile, it was found that the revolution of spin coating influenced the morphology of films obviously. Under the excitation at 396 nm, NaGd(WO 4 ) 2 :Eu 3+ /Bi 3+ films showed characteristic emission bands originating from 5 D 0 → 7 F j ( j = 1, 2, 3, and 4) transitions of Eu 3+ ions. It was also found that the excitation wavelength has great effect on the emission intensity.
研究领域:
材料科学
·
光电技术
·
光子学
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2024
·Vol. 130
·期 4
·1-9
·
IF 2.5
Qian Di,Jin Yahong,Li Yanmei,Wu Haoyi,Hu Yihua
Phosphor-converted light-emitting diodes (pc-LEDs) with broadband near-infrared (NIR) emissions have garnered significant research interest. Their performance is primarily determined by the type of NIR phosphor used. Herein, a broadband NIR-emitting phosphor, Y 3 Sc 2 Al 3 O 12 :Cr 3+ , is synthesized. The blue-light excitation of the Y 3 Sc 2 Al 3 O 12 :Cr 3+ phosphor produces a broadband emission spectrum ranging from 640 to 1000 nm with a full width at half maximum (FWHM) of 113 nm. The NIR emission intensity maintains approximately 50% of the initial room-temperature intensity at 423 K. The structure–property relationship is also comprehensively studied. Encapsulating the as-obtained NIR phosphor into prototype pc-LEDs produces an NIR output power of 58.1 mW at a 1230 mA driving current and a photoelectric conversion efficiency of 3.5% at 30 mA. Finally, night-vision applications are implemented using the as-fabricated pc-NIR-LEDs device.
研究领域:
材料科学
·
光电子学
·
固态照明
·
红外技术
·
荧光粉化学
✓ 已验证
DOI
高影响因子
DYES AND PIGMENTS
·
2022
·
IF 5.122
Jiaqi Dang,Ruifeng Zhu,Wenhui Fang,Ye Hu,Ying Wu,Shixian Xin,Min Li,Bozhen Chen,Hong Zhao,Zengxi Li
It is very crucial to develop a simple and fast-responsive sensor for the detection of water content in organic solvents . Herein, three different europium-organic frameworks (Eu-MOFs): amorphous Eu-2-aminoterephthalic acid (amEu-NH 2 BDC), crystalline Eu-2-aminoterephthalic acid (cryEu-NH 2 BDC) and amorphous Eu-1,4-benzenedicarboxylic acid (amEu-BDC) are synthesized, respectively. amEu-NH 2 BDC is employed as fluorescence probe for the determination of water in ethanol. Results indicate that amEu-NH 2 BDC exhibits good performance due to its dual-wavelength fluorescence (FL) with the ligand (NH 2 BDC)-centered blue luminescence at 430 nm and Eu-centered red luminescence at 615 nm. With the increase of water contents in ethanol, the emission intensity at 430 nm increases dramatically, while that at 615 nm decreases under a single excitation at 270 nm. By measuring the ratio of emission intensity at 430 nm and 615 nm (I 430 /I 615 ), a wide concentration range from 1% to 99.5% water in ethanol is obtained with a lower detection limit value of 0.024% (S/N = 3). Besides, in the presence of water in ethanol, the fluorescence color of amEu-NH 2 BDC changes from red to blue under 365 nm UV light. Thus, the visual device for the detection of water is realized by using amEu-NH 2 BDC. Combined with the fluorescence lifetime and density functional theory, it is shown that red luminescence weakens due to dynamic quenching and non-radiative vibration energy transfer, and blue luminescence is enhanced due to the hydrogen bonding between water and carboxyl groups in the ligand, which enhances the intramolecular charge transfer process. The proposed method has characteristics of rapid response, excellent stability, high sensitivity and selectivity. Importantly, it can be successfully applied to monitor the content of water in white spirit samples.
研究领域:
材料科学
·
分析化学
·
光学传感
✓ 已验证
DOI
高影响因子
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