Materials
·
2017
·Vol. 10
·期 2
·149
·
IF 2.654
Liang Wang,Da-Gang Guo
A UV-curable poly(butyl fumarate) (PBF)/poly(propylene fumarate)-diacrylate (PPF-DA) hybrid material with good performance for LED encapsulation is introduced in the paper. They have been prepared by radical polymerization using PBF and PPF-DA macromers with a UV curing system. PBF and PPF-DA were characterized by Fourier-transform infrared (FT-IR) and H-nuclear magnetic resonance (1H NMR). The thermal behavior, optical and mechanical properties of the material were examined by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), ultraviolet-visible spectroscopy (UV–vis), and a material testing system mechanical testing machine, respectively. The results indicated that the hybrid material has a suitable refractive index (n= 1.537) and high transmittance (99.64% in visible range) before/after thermal aging. With the increasing of the double bond ratio from 0.5 to 2, the water absorption ratios of the prepared encapsulation material were 1.22%, 1.87% and 2.88%, respectively. The mechanical property experiments showed that bonding strength was in the range of 1.86–3.40 MPa, tensile-shear strength ranged from 0.84 MPa to 1.57 MPa, and compression strength was in the range of 5.10–27.65 MPa. The cured PBF/PPF-DA hybrid material can be used as a light-emitting diode (LED) encapsulant, owing to its suitable refractive index, high transparency, excellent thermal stability, lower water absorption, and good mechanical properties.Keywords:poly(butyl fumarate)-based polymer;composites;characterization;UV-curing;LED encapsulant
研究领域:
材料科学
·
高分子化学
·
光电子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2025
·
IF 3.6
Mingjun Zhao,Chongyun Shao,Weichang Li,Danping Chen,Wei Chen
A strong near-infrared (NIR) fluorescent borate glass doped with tellurium (Te) clusters was developed, and spectral properties were studied. Under an oxidizing atmosphere, Te clusters could not be formed; however, under a reducing atmosphere, broadband Te-cluster NIR emission covering 600–1400 nm was successfully achieved, with a peak centered at 900 nm and a full width at half maximum (FWHM) of 270 nm. The findings demonstrated that adjusting the glass composition and TeO 2 doping concentration can significantly enhance the NIR emission of Te-doped borate glass. Furthermore, the study revealed that the photoluminescence performance of this material is highly sensitive to both temperature and excitation wavelength, demonstrating its potential for tunable luminescent properties. A NIR glass-converted LED (gc-LED) device was fabricated by integrating Te-cluster-doped borate glass with a commercial 460 nm LED, demonstrating its potential applications in night vision, non-destructive testing, and biomedical imaging. This research provides a theoretical foundation and technical pathway for developing novel ultra-broadband NIR emission glass materials .
研究领域:
材料科学
·
光学材料
·
光子学
·
固态照明
·
近红外技术
✓ 已验证
产品关联
DOI
高影响因子
Materials Advances
·
2021
·Vol. 2
·期 4
·1320-1327
·
IF 0
Yao Liu,Aifei Wang,Jiajing Wu,Chuying Wang,Ziliang Li,Guangcai Hu,Shiqi Sui,Jia-Xin She,Wen Meng,Weiqiang Li,Zhengtao Deng
In recent years, two-dimensional (2D) layered tin halide perovskites have attracted much attention due to their excellent luminescence properties compared with their three-dimensional (3D) analogs. Here, we synthesized 2D perovskites of the form (RNH3)2SnBr4 through a facile hot-injection approach without the use of toxic tri-n-octylphosphine (TOP) as the solvent. We found that these compounds have strong photoluminescence (PL) emission with high PL quantum yields (QY) of 35% ((C6H13NH3)2SnBr4), 82% ((C8H17NH3)2SnBr4), 60% ((C12H25NH3)2SnBr4) and 50% ((C18H35NH3)2SnBr4). Among them, ((C6H13NH3)2SnBr4) was synthesized for the first time; however, (C18H36NH3)2SnBr4 perovskites showed the best stability with a PL QY decrease of less than 1% after 30 days under ambient air and humidity conditions. In addition, other 2D (C8H17NH3)2SnX4 (X = Br, I, or mixture) perovskites were prepared by adjusting the halide ratio, resulting in spectral tunability from yellow to red. Interestingly, through Zn2+ doping, the morphology became more uniform, and the PL stability was significantly improved. Finally, we used Zn2+-doped (C8H17NH3)2SnBr4 yellow phosphor to fabricate UV-pumped yellow LEDs. We expect these 2D perovskites to be promising phosphors in future solid-state lighting and display technologies.
研究领域:
材料科学
·
光电技术
·
化学
✓ 已验证
产品关联
DOI
CATALYSIS COMMUNICATIONS
·
2020
·
IF 3.612
Mingcai Yin,Jiangfan Sun,Yixian Li,Yimin Ye,Kaiyue Liang,Yaoting Fan,Zhongjun Li
MoS 2 is a promising catalyst for hydrogen evolution reaction, whereas the inherent defects of limited active sites for H 2 evolution and poor conductivity impede its practical application. Herein, low-cost and available activated carbon (denoted as C) was introduced and MoS 2 /C composite was prepared via a facile one-pot liquid-phased reaction. The MoS 2 /C exhibits an excellent photocatalytic hydrogen evolution activity (872.3 μmol/h) sensitized by Erythrosin B under LED light irradiation, which is about 1.8 times that of pure MoS 2 . Moreover, hydrogen evolution mechanism and reasons for the enhanced performance of MoS 2 /C were proposed based on the results of photoluminescence spectra and photoelectrochemical tests.
研究领域:
材料科学
·
光催化
·
氢能
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Jianxu Wang,Yan Xie,Junlan Guo,Xuemei Yao,Xue Geng,Jing Gao,Xuyao Feng,Zijing Zhou,Yuanyuan Liu,Bin Deng,Ruijin Yu
Novel apatite-type NaCa 3 Bi(PO 4 ) 3 F: x Sm 3+ (0.01 ≤ x ≤ 0.30) orange-red-light phosphors were synthesized through the solid-state method at high temperature. The crystal structure, energy band structure , density of state, phase purity, particle morphology , photoluminescence properties, thermostability, and luminescence decay of the phosphors were comprehensively characterized. When λ ex = 404 nm, the optimal NaCa 3 Bi(PO 4 ) 3 F:0.05 S m 3+ phosphor showed the orange-red emission (597 nm). The NaCa 3 Bi(PO 4 ) 3 F:Sm 3+ phosphors exhibited abnormal thermal quenching properties as their emission intensity increased by about 2.57% from 300 to 380 K. Their intensity at 440 K was still 1.01-fold stronger than that at room temperature. The abnormal thermal quenching mechanisms were well explained via the coordinate configuration scheme. The thermal activation energy ( E a ) was calculated to be 0.79 eV. The color purity of all the phosphors reached 99.9%. Ultimately, a white light-emitting diode (w-LED) was fabricated based on the tri-color RGB method. The color rendering index and the chromaticity coordinates of the fabricated w-LED were 89 and (0.310, 0.319), respectively. Thus, these high thermostability NaCa 3 Bi(PO 4 ) 3 F:Sm 3+ orange-red phosphors can be potentially used in w-LED applications.
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
OPTICAL MATERIALS
·
2025
·
IF 4.2
Houteng Zhao,Xuemei Yao,Xinyi Tian,Liqing Guo,Siyu Cheng,Yilian Ran,Dongze Li,Di Gao,Hanxin He,Shu-Wei Chen,Xiang Liu,Yuchen Yang,Ruijin Yu
A series of novel single-phase oxyapatite-type Eu 3+ -doped Ba 2 La 3 (SiO 4 ) 2 (PO 4 )O (BLSPO) phosphors for the first time were synthesized by means of a high-temperature solid-state reaction. The prepared phosphors were analyzed in terms of phase purity using X-ray diffraction (XRD) and Rietveld refinement. The BLSPO:Eu 3+ phosphors pertain to the hexagonal crystal structure and the P 6 3 / m (No.176) space group. BLSPO as an indirect bandgap semiconductor, has been experimentally determined to possess a bandgap energy of 4.85 eV, while theoretical calculations yield a value of 4.45 eV. The photoluminescence excitation of BLSPO:Eu 3+ exhibits the highest peak at 393 nm. Four distinct characteristic peaks are observed in the emission spectrum of BLSPO:Eu 3+ . Notably, the peak at 618 nm shows the highest emission intensity due to the radiative transition from 5 D 0 - 7 F 2 . By varying doping concentrations, it was determined that an optimal concentration of 0.30 mol Eu 3+ resulted in phosphors, with high color purity up to 100 %. At 420 K, the emission intensity of the BLSPO:0.30Eu 3+ phosphor can still maintain 66.8 % of the starting intensity observed at 300 K. The internal quantum efficiency (IQE) of BLSPO:0.30Eu 3+ is 74.7 %. The Commission International de L'Eclairage (CIE) color coordinate of w-LED was measured as (0.328, 0.334), correlating to correlated color temperature (CCT) of 5706 K and exhibiting a good color rendering index (CRI, R a = 92). Additionally, the BLSPO:0.30Eu 3+ phosphor surface was functionalized with oleic acid (OA) (BLSPO:0.30Eu 3+ @OA) to help identify fingerprint details at levels I-III details with high contrast and high resolution. Excellent visualization of latent fingerprints (LFPs) was observed on different substrates. In conclusion, high-efficiency oxyapatite-based BLSPO:Eu 3+ phosphors have attractive potential for w-LED and LFP applications.
研究领域:
材料科学
·
光学
·
法医学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Optical Materials
·
2019
·Vol. 7
·期 12
·1900093
·
IF 7.125
Sisi Liang,Guogang Li,Peipei Dang,Yi Wei,Hongzhou Lian,Jun Lin
Currently, Mn 4+ -activated red-emitting materials are the research hotspot due to their promising application in phosphor-converted white light-emitting diodes (w-LEDs). Here, a typical cation substitution strategy is reported to optimize Mn 4+ -doped germinate phosphor for improving luminescence performances. The effect of cation substitution for Ge 4+ ions by Ti 4+ , Sn 4+ , and Si 4+ ions on lattice structure, photoluminescence properties, and thermal stability of the as-prepared Mn 4+ -doped germinates is systematically investigated. A significant improvement of emission intensity with Ti 4+ doping should benefit from the resonance emission enhancement effect. Some lattice distortion defects contribute to the thermal stability enhancement, which plays a role in driving the excited phonon traps to compensate the energy loss of nonradiative transition. Surprisingly, abnormal variation in intensity of anti-Stokes and Stokes emission peaks with changing temperature is first observed, revealing a potential application in thermometry. The electroluminescence performances of as-fabricated w-LED devices using Mg 14 Ge 5 Ti 0.5 O 24 :Mn 4+ red phosphor are evaluated, which possess higher color rendering index ( R a = 87.3) and luminous efficiency (109.42 lm W −1 ) as well as lower color correlated temperature (3566 K) than those using Cs 2 GeF 6 :Mn 4+ and CaAlSiN 3 :Eu 2+ red phosphors. The results reflect the superiority of the studied phosphor in w-LEDs and optical thermometry areas.
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
ANALYTICA CHIMICA ACTA
·
2023
·
IF 6.2
Dongmei Liu,Yu Xiong,Hui Zeng,Jin Xu,Biyu Tang,Yan Li,Min Zhang
Background Capillary electrophoresis (CE) with capacitively coupled contactless conductivity detection (C 4 D) is widely used for water quality monitoring. However, there is currently no reported CE method for detecting total dissolved nitrogen (TDN), a crucial parameter for assessing water eutrophication . One challenge is the high sulfate concentration (100 mM) introduced during persulfate digestion, leading to overlap of nitrate (from TDN) and poor electrical stacking of nitrate in CE-C 4 D analysis. Results We introduced an in-capillary UV-LED induced photoreaction to convert nitrate to nitrite, which can be baseline-separated from sulfate via the CE method, enabling accurate quantification of nitrate concentration derived from nitrite. A 2 nL post-persulfate digested sample solution within a fused silica capillary was exposed to UV-LED irradiation at the capillary tip. Subsequently, photoreduction-produced nitrite was electrophoretically separated from sulfate in an acidic buffer (pH = 3.7) within the same capillary, followed by contactless conductivity detection. The nitrate-to-nitrite conversion efficiency was influenced by irradiation wavelength, power, and duration, reaching a maximum efficiency of 77.4% when employing two 230 nm LEDs for 5 min. For more general applications, two 255 nm LEDs were used, providing a conversion efficiency of (66.4 ± 3.3)% ( n = 11) for 5 min of irradiation. The proposed CE-C 4 D method exhibits a detection limit of 13 μM (0.18 mg N/L) and has been successfully employed for TDN determination in lake water samples. Significance This innovative approach not only enhances the attractiveness of the CE-C4D method for the determination of water quality indicators but also highlights the potential for integrating deep-UV LEDs into environmental analysis .
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Yue Su,Lifang Yuan,Bo Wang,Sijian Wu,Yahong Jin
Metal halide perovskites (MHPs) have sparked ongoing research interest due to their high-performance optoelectronic properties. However, blue-light excitable near-infrared (NIR) emitting MHPs is still inaccessible and the achievement of robust thermal-quenching resistance so far remains a huge challenge. In this work, we report on the synthesis of lead-free all-inorganic Mn 2+ -based perovskite-like single crystals using the designed nonstoichiometric precursor ratio. The special crystal structure endows Mn 2+ with efficient blue light excitation and red emission, which enables the capabilities of a good matching with commercial blue LED chips and an efficient sensitization for Ln 3+ emitters. The incorporations of Yb 3+ , Er 3+ , and Ho 3+ functionalize the CsMnCl 3 single crystals with multiple NIR emissions by virtue of feeding the energy from Mn 2+ to Ln 3+ via multi-channels. Most remarkable is the achievement of the robust thermal-quenching resistance, exhibiting (near-) zero-thermal-quenching and even anti-thermal quenching, of the Ln 3+ NIR emissions above room temperature . Finally, as a proof-of-concept study, a prototype of an NIR-LED device was fabricated. This work not only provides a general strategy to unlock the blue-light excitable NIR emission from f-f transitions of Ln 3+ ions, and a fundamental understanding of the sensitization-activation mechanisms in Ln 3+ -functionalized manganese (Ⅱ)-based perovskite-like phosphor, but also endows the MHPs with optical functionalities for the future high-potential applications, such as NIR phosphor-converted LEDs, and optical telecommunication.
研究领域:
材料科学
·
光电学
·
光子学
·
固体物理
·
无机化学
✓ 已验证
DOI
高影响因子
Materials Today Chemistry
·
2022
·
IF 7.613
Kaiyuan Deng,Yahong Jin,Lifang Yuan,Bo Wang,Haoyi Wu,Yihua Hu
Artificial light-emitting diode (LED) light source, regarded as a front-runner technology for the promoting of plant growth, has attracted much attention toward the burgeoning fertilizer-free indoor plant cultivation. It still remains a challenge that explore a far-red-emitting phosphor of high-thermal stability. Overall, we report a Mn 4+ ion-doped ordered double perovskite tungstates prepared by high-temperature solid-state reaction method in air. The crystal structure, morphology, and fluorescence properties were investigated and discussed in detail. The far-red emission of the optimized CaSrMgWO 6 :1%Mn 4+ , covering the wavelength region of 630–780 nm, matches the absorption ranges of the chlorophyll a and phytochrome (P fr ). The value of Dq/B is estimated to be 2.81. Most notable is the excellent thermal quenching resistance of the Mn 4+ emission, remaining 86.7% at 150 °C, thereby suitably fabricating a far-red LED device. The LED light-driven regulation of the physiological and biochemical changes enables a proof-of-concept garlic cultivation. The growth of weight, stem length, and root length of the garlic was significantly promoted with the extra supply of the far-red light. This work demonstrates that the as-obtained far-red-emitting phosphor holds a promising perspective for the phosphor-converted far-red LED light sources toward the flourishing fertilizer-free indoor plant cultivation.
研究领域:
材料科学
·
植物生理学
·
光电技术
·
农业工程
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Chenglong Xia,Jiahui Yang,Bingyang Zeng,Chunmiao Cui,Haoyuan Weng,Yue Guo,Xiaoguang Liu,Ling Li
This study successfully synthesized Na 5 Y(WO 4 ) 4 doped with Sm³⁺, Pr³⁺, and Tb³⁺ using a high-temperature solid-state method. Photoluminescence spectra revealed that Na 5 Y(WO 4 ) 4 :Sm³⁺ phosphors emits a strong red glow at 646 nm under the excitation of 405 nm, and has an extremely high quantum yield, suggesting their suitability for plant growth LED lighting applications. In contrast, Na 5 Y(WO 4 ) 4 :Pr³⁺ phosphors displayed a lower efficiency but still aligned well with the red-wavelength absorption spectra of plants. Additionally, Na 5 Y(WO 4 ) 4 :Tb³⁺ phosphors demonstrated strong green emission under UV light, indicating potential applications in fingerprint detection. The Site Occupancy Theory (SOT) was utilized to explain the preferential occupation of dopant ions, showing that Sm³⁺ and Tb³⁺ preferred Y1 sites, whereas Pr³⁺ favored Na2 sites.
研究领域:
材料科学
·
光学
·
农业科学
·
法医学
✓ 已验证
产品关联
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
危险品化学品经营许可证（带存储）