CERAMICS INTERNATIONAL
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2019
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IF 3.45
Xinwei Li,Hualan Xu,Xianming Xia,Feiyan Xie,Shengliang Zhong,Dekang Xu
Sc 2 W 3 O 12 is an important host matrix for rare-earth doped luminescence. However, the conventional method to prepare the material is solid-state reaction, which results into coarse and irregular morphologies. In this work, Eu 3+ doped Sc 2 W 3 O 12 phosphors with high crystallinity and pure phase were successfully synthesized via one-step hydrothermal method . It was found that the crystalline phase changed from Sc 2 W 3 O 12 phase to Na 4 Sc 2 (WO 4 ) 5 phase when the molar ratio between Sc(NO 3 ) 3 and Na 2 WO 4 decreased. The temperature-dependent X-ray diffraction analysis was performed to prove the negative thermal expansion property of Sc 2 W 3 O 12 . A systematic study on the effect of reaction time, temperature and Eu 3+ doping concentration was explored. It was also found that the as-prepared samples displayed tunable emission colors, ranging from blueish white to orange red. Particularly, the white light emission with the chromaticity coordinate of (0.3395, 0.3289) can be realized in Sc 2 W 3 O 12 : 5% Eu 3+ . What's more, the photoluminescence properties of the samples were investigated under different ambient temperatures between 97 and 280 K. The result clearly showed energy transfer between Eu 3+ and WO 4 2− . The above results suggested that Sc 2 W 3 O 12 :Eu 3+ can be excellent candidate for solid-state lasing, panel display and WLEDs.
研究领域:
材料科学
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光电
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发光材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Yuanyuan Fan,Shun Li,Daobin Zhu,Keyu Guo,Rangrang Fan,Chunfeng Dong,Yongtao Liu,Yong Li,Junshan Hu
The thermal quenching effect of photoluminescent materials greatly limits their practical applications in bioimaging, sensing, radiation detection, and photovoltaic devices. In this paper, the upconversion luminescence (UCL) of Sc 2 W 3 O 12 :Er 3+ /Yb 3+ was significantly improved by doping Ba 2+ ions. The study identifies that the optimal doping concentration of Ba 2+ ions within the negative thermal expansion (NTE) phosphors Sc 2 W 3 O 12 : Er 3+ /Yb 3+ is 0.03 mol, the green and red light intensities of Sc 2 W 3 O 12 : Er 3+ /Yb 3+ /Ba 2+ phosphor were increased by 32.76 times and 23.06 times. When the temperature rises from 298 K to 523 K, the NTE effect causes an abnormally increased luminous intensity. Utilizing fluorescence intensity ratio (FIR) technology, the temperature sensing characteristics of the Sc 2 W 3 O 12 : 0.30 Yb 3+ , 0.02 Er 3+ , 0.03 Ba 2+ phosphor were further examined, achieving maximum relative and absolute sensitivities of 1.24 % K −1 and 1.97 % K −1 , respectively.
研究领域:
材料科学
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无机化学
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光子学
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温度传感
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功能材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2018
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IF 3.779
Shuai Gao,Nan Zhao,Qinqin Liu,Yi Li,Guifang Xu,Xiaonong Cheng,Juan Yang
Owing to that, efficient cooling the chip demands a heat sink material possess high thermal conductivity and low CTE equivalent to the gallium arsenide (GaAs) or silicon (Si). Addressing this target, we have synthesized Sc 2 W 3 O 12 /Cu composites by hot-pressing sintering at 700 °C, which was based on the uniform submicron Sc 2 W 3 O 12 powder prepared for the first time. The resulting product not only possessed a low CTE (8.31 ppm/K, which was identical to GaAs of 6.2 ppm/K) and high thermal conductivity (243.99 W/m K), but also exhibited extremely stable CTE within a temperature range of 25 °C–300 °C and high Vickers hardness (234.32 HV) due to its uniform and nearly full dense microstructure. A ‘thermoelastic-micro-mechanics'model was used to predict the CTE quantitatively and the estimated values were in good agreement with the experimental CTE values. Moreover, the excellent compatibility of thermal properties between Sc 2 W 3 O 12 and Cu possesses an isolated spot in Ashby map based on CTE and thermal conductivity, and the as-synthesized composite exhibits nearly greatest thermal stability indicated via its low thermal distortion parameter (TDP).
研究领域:
材料科学
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热管理技术
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2022
·
IF 11.307
Pengcheng Wang,Zhiquan Xu,Xuefeng Liu,Haohan Wang,Bin Qin,Jinghuang Lin,Jian Cao,Junlei Qi,Jicai Feng
Negative thermal expansion (NTE) materials can offset the high expansion of metal brazing alloys, and play a key role in alleviating the residual stress and improving the mechanical properties of the joint . However, in Sc 2 W 3 O 12 reinforced AgCuTi composite filler, the strong interfacial reaction between active Ti and Sc 2 W 3 O 12 has become a bottleneck restricting the NTE behavior of Sc 2 W 3 O 12 . Herein, a novel strategy is proposed by designing a carbon barrier layer between active filler and Sc 2 W 3 O 12 materials. Under the guidance of experimental results and theoretical analysis, the interface evolution mechanism is proposed. The results show that the carbon barrier layer increases the diffusion path of Ti atoms and weakens the interfacial reaction. With the help of carbon barrier layer, Sc 2 W 3 O 12 gives full play to its NTE behavior during brazing, and the retention rate increases from 65.8% to 97.6%. Consequently, a highest shear strength of ∼77 MPa is achieved in the C/SiC-GH3536 joints by the designed composites filler, which is 1.3 times higher than that without carbon barrier layer and 3.2 times higher than that of AgCuTi filler. Our work opens the way for expanding the application of NTE materials in brazing process, and also provides new insights for the development of low-CTE composites.
研究领域:
材料科学
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连接技术
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热膨胀工程
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复合材料
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界面工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）