JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2017
·Vol. 28
·期 13
·9464-9470
·
IF 2.019
Xing Yangyang,Zhu Yingchun,Chang Chengkang,Wang Yunli,Wang Yang
Eu 2+ -doped β-Sialon phosphors with a composition of Eu
x
Si 5 Al 1− x
O z+ x
N 8−z− x
( x = 0.05, 0.06, 0.07) were synthesized in a new synthetic route using novel raw materials, such as nano-silicon dioxide (SiO 2 ), nano-carbon (C), and aluminum (Al). This is different from the prevailing method using Si 3 N 4 , AlN, and Al 2 O 3 to obtain β-Sialon phosphors. Compared with the conventional method, lower cost raw materials, simpler pretreatment and a relatively shorter reaction time are achieved. The phosphors show a high purity. All the phosphors exhibit green emission under ultra violet (UV) radiation. A broad band of excitation spectra implies the promising application in UV ray based green light-emitting diode (LED). Chromaticity coordinates of the β-Sialon: Eu 2+ phosphors demonstrate that it is accessible to obtain different green emissions from single phase of Eu 2+ -doped β-Sialon through adjusting Eu 2 O 3 concentration. Furthermore, the Eu
x
Si 5 Al 1− x
O 1 + x
N 7 − x
( x = 0.05) shows a better thermal stability than the commercial green-emitting silicate phosphor. These results indicate a promising prospect for this efficient and economic route in preparing β-Sialon: Eu 2+ phosphors, and the phosphors are a highly promising candidate for LED applications.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Qin Liu,Zengbin Yin,Fuzhou Guo,Juntang Yuan
β-SiAlON ceramic tool materials were fabricated via spark plasma sintering using binary sintering additives (SmF 3 -Sm 2 O 3 ). The effects of SmF 3 addition and sintering temperature on the densification, phase composition, microstructure and mechanical properties were studied. Furthermore, the corrosion behavior of β-SiAlON ceramic tool materials due to excessive SmF 3 at high sintering temperatures (≥1700 °C) was revealed. The results indicated that SmF 3 could promote the densification and generation of β-SiAlON. Higher SmF 3 content and sintering temperature increased the aspect ratio and average grain size of β-SiAlON, which made fracture toughness increase and Vickers hardness decrease. The best density, fracture toughness and hardness of β-SiAlON ceramic tool materials were 3.204 g/cm 3 , 6.45 ± 0.07 MPa m 1/2 and 16.72 ± 0.09 GPa. However, β-SiAlON was corroded by excessive SmF 3 during high temperature sintering, resulting in deterioration in densification and properties.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2019
·
IF 4.029
Jie Zhang,Xiangcheng Li,Wei Gong,Pingan Chen,Boquan Zhu
Columnar β-Sialon bonding phases were in situ synthesised in Al 2 O 3 -C refractory composites and their growth mechanism was simulated based on first-principles calculations. The experimental results indicated that the addition of Fe 2 O 3 as a catalyst accelerated the transformation of Si 3 N 4 to β-Sialon, resulting in a well-developed columnar structure. The (100) facet was the primary surface for crystal growth during the transformation process of Si 3 N 4 into β-Sialon. According to first-principles calculations, the surface energy of the (100) facet decreased greatly due to the substitution of (Si, N) pairs with (Al, O). The catalyst could promote the adsorption of gaseous phases on the (100) facet of Si 3 N 4 and decreased the gas adsorption energy of both SiO and Al 2 O. Owing to the presence of in situ synthesised columnar β-Sialon bonding phases, the residual crushing strength of Al 2 O 3 -C refractory composites after 5 thermal shock cycles increased by 25.1%.
研究领域:
材料科学
·
计算化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2012
·
IF 1.751
Lin Gan,Zhi-Yong Mao,Yu-Qiang Zhang,Fang-Fang Xu,Ying-Chun Zhu,Xue-Jian Liu
Ce 3+ -doped β-SiAlON blue phosphors with composition of Ce x Si 6− z Al z O z N 8− z (0.2≤ z ≤4) at a fixed x =0.01 were synthesized by the gas pressure sintering method. The phases and photoluminescence properties were found to be directly correlated to the z value. Higher z value would result in the formation of AlN polytypoid impurity phases. The optimal z value resides in the range 0.3≤ z ≤0.5, by which high purity of β-SiAlON phase, good crystallinity and fine grain size were obtained, leading to the best luminescence properties. These phosphors could be a good candidate for application in white light-emitting diodes using InGaN-based near–ultraviolet chips.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2015
·Vol. 7
·期 26
·11393-11400
·
IF 7.394
Lin Gan,Fang-Fang Xu,Xiong-Hui Zeng,Zuo-Sheng Li,Zhi-Yong Mao,Ping Lu,Ying-Chun Zhu,Xue-Jian Liu,Lin-Lin Zhang
The critical doping structures of rare-earth atoms in the promising β-SiAlON phosphors have long been argued owing to the lack of direct evidence. Here, the exact locations and coordination of the Ce rare-earth atoms in the β-SiAlON structure have been examined using an atom-resolved Cs-corrected scanning transmission electron microscope. Three different occupation sites for the Ce atoms have been directly observed: two of them are in the structural channel coordinated with six and nine N(O) atoms, respectively; the other one is the unexpected substitution site for Si(Al). The chemical valences and stabilities of the doping Ce ions at the different occupation sites have been evaluated using density functional calculations. Correlation of the different doping structures with the luminescence properties has been investigated by the aid of cathodoluminescence (CL) microanalysis, which verifies the different contribution of the interstitial trivalent Ce ions to the light emission while no luminescence is observed for the substitutional doping of quadrivalent Ce.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2015
·
IF 2.719
Qian Liu,Qi Lu,Guanghui Liu,Qinhua Wei
β-SiAlON:Eu 2+ phosphors synthesis usually requires higher temperatures and higher nitrogen pressure conditions. In the present research, a low temperature technique has been developed to synthesize both β-SiAlON and Eu-doped β-SiAlON fibers by electrospinning combined with carbothermal reduction nitridation (CRN). The carbon sources used as reductant in CRN procedure have been optimized to effectively produce a well-crystallized β-SiAlON phase at lower temperatures of 1370–1500 °C. Additionally, through adding sucrose and covering activated carbon powders on the top of fiber precursor layers, the highly-pure β-SiAlON and β-SiAlON:Eu 2+ fibers could be obtained. The pyrolysis behavior of fiber precursors, crystalline phase, morphology, and UV excited luminescence properties of the produced ceramic fibers were also studied by using TG–DSC measurement, XRD analysis , SEM observation, and spectrometer method. The resultant fibers exhibit a smooth surface and an uniforme morphology with a substantial length. Moreover, the β-SiAlON:Eu 2+ fibers thus prepared show a blue light emission peaked at 470 nm under UV excitation.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2026
·
IF 6
Zhigang Xu,Lei Xue,Zhongwei Liu,Kaiping He,Qiang Shen,Chuanbin Wang
This study systematically investigates the effects of varying Y 2 O 3 /ZrO 2 additive ratios on the phase evolution, microstructural characteristics, densification, mechanical properties, and tribological performance of β-Sialon ceramics fabricated via spark plasma sintering. The results demonstrate that both Y 2 O 3 and ZrO 2 promote the formation and densification of β-Sialon. Specifically, ZrO 2 facilitates the in-situ reaction with Si 3 N 4 and AlN to form ZrN, while Y 2 O 3 enhances the densification process through liquid phase formation. Notably, the content of in-situ formed ZrN decreases with the increase of Y 2 O 3 addition. Compared to the single addition of Y 2 O 3 , the optimized Y 2 O 3 /ZrO 2 ratio enables the formation of fine β-Sialon grains, well-dispersed ZrN particles, and minimal grain boundary phases. When 2 wt% Y 2 O 3 and 4 wt% ZrO 2 (SY2Z4) were added, the β-Sialon ceramic achieved an optimal balance of properties, where the Vickers hardness and fracture toughness reached 17.3 GPa and 6.7 MPa m 1/2 , respectively, representing increases of 27.2% and 28.9% compared to the sample with the sole addition of 6 wt% Y 2 O 3 (SY6). In terms of tribological properties, the SY2Z4 sample exhibits a significantly reduced coefficient of friction (0.582), wear volume loss (0.89 × 10 −2 mm 3 ), and wear rate (0.25 × 10 −5 mm 3 /(N·m)), which are 12.87%, 91.76%, and 91.67% lower than those of SY6, respectively. The results also indicate that abrasive wear is the dominant wear mode, and the in-situ formation of a protective tribofilm on the worn surface of SY2Z4 further contributes to its superior wear resistance. This work provides a feasible strategy for the microstructural regulation and performance optimization of β-Sialon ceramics via tailoring rare earth oxide/transition metal oxide additive systems, which holds great potential for extending their applications in high-wear-resistance engineering fields.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2023
·
IF 6.4
Bo Dong,Chengji Deng,Jun Ding,Hongxi Zhu,Qian Wang,Yong Zhang,Chao Yu
In this investigation, we have employed a novel approach to fabricate β–Sialon/Ti(C, N) composites through the nitridation treatment of Ti 3 SiC 2 powder. At temperatures ranging from 1373 to 1773 K, the reaction process was subjected to a comprehensive analysis to explore the transformation of phase and microstructure. The findings unequivocally highlight the influence of α–Al 2 O 3 presence and the high specific surface area of Ti 3 SiC 2 powder, resulting in distinctive phase and structural evolutions post nitridation, distinctly different from those observed in bulk Ti 3 SiC 2 . The β–Sialon/Ti(C, N) composites produced via this innovative method exhibit uniform local chemical composition and meticulous regulation of grain morphology. Moreover, the synthesis mechanism of β–Sialon/Ti(C, N) composites under nitrogen ambiance was thoroughly discussed. This straightforward approach has the potential for extensive–scale synthesis of β–Sialon/Ti(C, N) composites, offering promising avenues for their application in developing high–performance refractories or structural ceramics tailored to withstand severe high–temperature environments.
✓ 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）