Materials Chemistry Frontiers
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2019
·Vol. 3
·期 10
·2120-2127
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IF 0
Qiang Zhang,Xicheng Wang,Zuobin Tang,Yuhua Wang
A novel blue-emitting phosphor, Na3ScSi2O7:Ce3+ (NSSO:Ce3+), was synthesized with a solid-state method at low temperature successfully. Its crystal structure, band structure, and photoluminescence and cathodoluminescence properties were researched in detail. The phase formation and the crystal structure were confirmed by powder X-ray diffraction analysis and the Rietveld refinement method, respectively. Under the excitation of n-UV light, the optimal NSSO:0.02Ce3+ phosphor can yield blue emission centered at 452 nm with a high quantum efficiency of 50.9%. The PL intensity of the NSSO:0.02Ce3+ phosphor remains at 71.46% of the initial value when the temperature is increased from room temperature to 150 °C, indicating good thermal stability. A WLED lamp was obtained by combining a 360 nm n-UV chip with Sr2SiO4:Eu2+, (Ca, Sr)AlSiN3:Eu2+ and NSSO:0.02Ce3+ phosphors, in which the color coordinates, CCT and CRI are (0.360, 0.348), 4409 K and 90.9, respectively. Moreover, under low voltage electron bombardment, the phosphor can emit blue emission with high luminescence intensity, current saturation and resistance. All the results indicate that the NSSO:Ce3+ phosphor shows much potential for the application of both WLEDs and field emission displays (FEDs). Our research has also offered a new insight and perspective that using Sc-based sorosilicates as host can be an appropriate strategy for developing excellent inorganic luminescence materials.
研究领域:
材料科学
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光学工程
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无机化学
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固态照明
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显示技术
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DOI
JOURNAL OF LUMINESCENCE
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2025
·
IF 3.6
Yingnan Dong,Yumeng Jia,Kenan Xu,Xu Sun,Jing Wang,Zhongxiang Shi,Yanchen Liu
In order to expand the multi-scene application of rare earth doped luminescent materials in the field of blue light illumination, a series of Ce 3+ doped Na-β″-Al 2 O 3 phosphors were prepared by solid-state method with Na-β″-Al 2 O 3 as matrix. The crystal structure, micro-morphology, optical properties and thermal stability were investigated systematically. The results show that the activated ion Ce 3+ in the prepared Na-β″-Al 2 O 3 : x Ce 3+ phosphor replaces the Al 3+ (CN = 6) lattice in the crystal, and with a outstanding blue light emission. In addition, the thermal stability of Na-β″-Al 2 O 3 : 0.05Ce 3+ phosphor is analyzed by variable temperature spectrum, and its luminescence intensity at 573K can reach 71.55 % at room temperature. Finally, Na-β″-Al 2 O 3 : 0.05Ce 3+ phosphors are packaged with 330 nm n-UV LED chips to obtain high quality blue LED devices. With its high color rendering index (81.60), low color temperature (2886 K) and good color consistency, it provides a theoretical basis for the application of Na-β″-Al 2 O 3 -based phosphors in blue LED devices, and makes it show great application potential in the field of solid-state blue spectral lighting.
研究领域:
材料科学
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固体化学
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发光材料
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照明工程
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无机功能材料
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2011
·Vol. 123
·期 5
·2706-2714
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IF 1.24
Guang Zhu,Jingkun Xu,Ruirui Yue,Baoyang Lu,Jian Hou
Relatively scant work was related to polynaphthalene (PN) and its derivatives because of the unique nonlinear optical properties which make PN and its derivatives owning potential applications in various domains. According to relevant studies, the pursuit for the synthesis of high quality PN films is a great challenge for the applications of PN. To achieve high quality polymer films, three bridged naphthalene derivatives were designed, and finally two crosslinked PN exhibiting space network were electrosynthesized, respectively, by direct anodic oxidation from 1,6-bis(naphthalen-2-yloxy)hexane and 1,4-bis((naphthalen-2-yloxy)methyl)benzene in mixed electrolyte of dichloromethane containing boron trifluoride diethyl etherate. Furthermore, as-formed conducting films were characterized by cyclic voltammetry, spectroscopic analysis, thermal analysis, and scanning electron microscopy. And the series of characterizations indicated that films hold high stability and good blue-light-emitting property. Meanwhile, these polymer films were smooth, shiny, and flexible easily being processed into various shapes by conventional mechanical methods. Consequently, these high quality PN films will facilitate their potential applications as blue-light-emitting materials in organic light-emitting diode. Because di(naphthalen-2-yl) terephthalate was difficult to electropolymerize, the effects of bridged spacers to polymerization were also discussed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
研究领域:
材料科学
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化学
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产品关联
DOI
高影响因子
OPTICAL MATERIALS
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2023
·
IF 3.9
Hua Ye,Denghui Liu,Fen Liu,Liangyuan Chen,Wei Hu,Yu Bai,Jiali Rao,Dehan Wu,Xinyi Cai,Shi-Jian Su
A series of light-emitting dendrimers T42Bn, T24Bn, T26Bn and T35Bn based on electron-donating units of the second-generation butyicarbazoles (G2Cz) as dendrons and electron-withdrawing core of tripyridylbenzene (TPB) were designed and synthesized. The desirable blue luminogens were obtained due to the rational molecular design based on the twisted skeleton of all the molecules despite the donors of G2Cz moieties connected to the central acceptors of TPB via a para-phenylene bridge. Their thermal, photophysical, density functional theory calculation and electrochemical properties were fully investigated. Thanks to the excellent thermal stability, film-forming ability as well as the favourable energy levels of the dendrimers, efficient solution-processed hybrid white organic light-emitting diodes (WOLEDs) were achieved by employing these blue dendrimers and the orange emitter of (acetylacetonato)-bis[2-(thieno [3,2-c]pyridin-4-yl)phenyl]iridium(III) (PO-01) as an emitting layer (EML). Among them, the device based on T42Bn exhibited the highest maximum current efficiency (CE max ) of 10.25 cd/A with a maximum external quantum efficiency (EQE max ) of 3.94% and Commission International de I'Eclairage (CIE) coordinates of (0.34, 0.39), benefiting from the largest ƞ PLQY and the highest electron transport capability of T42Bn and thus the enhancement of charge carrier balance in the device. In addition, the CIE coordinates of all the single-emitting-layer fluorescence/phosphorescence hybrid devices are very close to the benchmark white region of (0.33, 0.33). Our findings demonstrate the potential candidates of the solution-processable blue dendronized emitters for applications in full-color flat-panel displays and white lighting.
研究领域:
材料科学
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光电化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
·
IF 13.273
Tao Hua,Yu-Chun Liu,Chih-Wei Huang,Nengquan Li,Changjiang Zhou,Zhongyan Huang,Xiaosong Cao,Chung-Chih Wu,Chuluo Yang
Highly efficient blue thermally activated delayed fluorescence (TADF) materials with high horizontal dipole orientation (Θ // ) remain a big challenge due to the concentration quenching effects and serious efficiency roll-offs in their corresponding organic light-emitting diodes (OLEDs). We herein report two novel TADF compounds, namely 2TDBA-SBA and TDBA-SBA, which were facilely synthesized by utilizing a rigid oxygen-bridged cyclized triarylboron-based unit (TDBA) as the acceptor and a spiro acridine (SBA) as the donor. Benefiting from the rigid and planar skeleton of the acceptor and the linear molecular shape, high Θ // s and photoluminescence quantum yields (PLQYs) of ∼ 90% were achieved. Significantly, TDBA-SBA exhibited excellent TADF properties with a short delayed fluorescence lifetime of only 684 ns and narrow full-width at half-maximum (FWHM) of 44 nm in solution state, accompanied by the high PLQYs of over 80% at high doping concentrations, manifesting the alleviated exciton quenching effects. Consequently, OLEDs based on TDBA-SBA achieved a high maximum external quantum efficiency (EQE) of 29.3% and a maximum brightness of 27663 cd cm −2 . Importantly, an EQE over 20% was realized even at the high brightness of 10000 cd cm −2 , signifying a small efficiency roll-off.
研究领域:
材料科学
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光学
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化学
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DOI
高影响因子
SYNTHETIC METALS
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2019
·
IF 2.87
Chenglian Hu,Chunchun Fei,Hongji Jiang
Two blue light emitters M-2EtCz and P-2EtCz based on carbazole and triphenylphosphine oxide were synthesized and characterized. The 5% weight loss temperatures of emitters M-2EtCz and P-2EtCz solid powder were 437 and 495 °C, and their photoluminescent quantum yield in solution were 53.93 and 75.78%, which were both significantly improved to those of parent EtCz-Ph . The introduction of triphenylphosphine oxide into EtCz-Ph can lower the lowest unoccupied molecular orbital levels of emitters M-2EtCz and P-2EtCz , while keeping their highest occupied molecular orbital levels unchanged. All the emitters exhibited blue light emission with aggregation-induced enhanced emission characteristic. The non-doped deep blue light-emitting diodes with maximum external quantum efficiencies of 2.68% were obtained for M-2EtCz , and the electroluminescent color purity of P-2EtCz was better than that of M-2EtCz . The doped device hosted by P-2EtCz achieved a maximum brightness of 10,891 cd/m 2 , external quantum efficiency of 2.04% and current efficiency of 5.65 cd/A.
研究领域:
有机电子学
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材料科学
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光电技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）