CERAMICS INTERNATIONAL
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2025
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IF 5.6
Zhiwei Xia,Yuhan Wang,Rujun Yang,Mengdi Xu,Cunjian Lin,Zhongyuan Li,Ying Lv,Xiaopeng Chi,Shihai You
The interstitial site engineering that purposely creates interstitial luminescent centers in suitable hosts has become an intriguing strategy in designing novel inorganic phosphors. However, effectively tuning the photoluminescence of interstitial activators remains tough challenging at this stage. Here, we demonstrate the effective modulation of interstitial luminescence in inorganic phosphor. In detail, the blue emission band ( λ em = 446 nm) of interstitial Eu 2+ doped α -cristobalite (SiO 2 :Eu 2+ ) is largely enhanced and broadened via a partial, aliovalent substitution of Si 4+ by Al 3+ . After introducing Al 3+ ions into SiO 2 lattice, the full width at half maximum of the blue emission band increase from 59 to 76 nm with a triple growth in quantum efficiency (10.82% → 35.56%). Moreover, the thermal stability improves significantly with a high emission retention of 60% at 325 °C (SiO 2 :0.06Al 3+ ,0.005Eu 2+ ), far higher than that of the parent SiO 2 :0.005Eu 2+ (30%). Encapsulating blue-emitting SiO 2 :Al 3+ ,Eu 2+ along with two commercial green and red phosphors on an ultraviolet LED chip ( λ em = 375 nm), a white LED device with high color rendering index (Ra > 90) was successful fabricated, showing the great potential of this phosphor for achieving high-quality white LED lighting. This study not only provides a promising bule emitter but also sheds light on modulating interstitial luminescence properties in inorganic phosphors.
研究领域:
材料科学
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2015
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IF 2.605
Yi Ding,Xirui Lu,Hui Dan,Xiaoyan Shu,Shuai Zhang,Tao Duan
Zr 1− x Nd x SiO 4− x /2 (0≤ x ≤0.1) ceramics were prepared by solid-state reaction method. The effects of Nd content on the phase structure of the ceramics were investigated. The chemical durability of Nd-doped zircon ceramic waste forms was also examined. The results show that the ceramics with x <0.04 show homogeneous single zircon phase, while the samples with x ≥0.04 e x hibit coexistence of two crystal phases (zircon and Nd 2 Si 2 O 7 ). The bulk density of the Nd-doped zircon ceramics increases with the increase in neodymium content. Moreover, the normalized element release rates of Nd element in Nd-doped zircon ceramics firstly decrease with leaching time and almost no change after 14 days (~10 −4 g m −2 d −1 ), demonstrating its good chemical durability. These results indicate that the obtained zircon ceramics waste forms are promising candidate for immobilization of trivalent actinides.
研究领域:
材料科学
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核废物管理
✓ 已验证
DOI
高影响因子
International Journal of Applied Ceramic Technology
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2024
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IF 1.8
Yansong Liu,Wenbo Li,Yongsheng Liu,Yu Pan,Yejie Cao,Xiang Zheng,Jian Chen,Yijiang Zeng
In this work, alumina was selected as the second phase reinforced fused quartz ceramics and SiO 2 –Al 2 O 3 composite ceramics were fabricated via digital light processing (DLP) 3D-printing. The effect of the sintering procedure on the mechanical and dielectric properties of SiO 2 –Al 2 O 3 composite ceramics were investigated in detail. The results show that the amount of cristobalite precipitation is the key factor affecting the properties of composite ceramics. The amount of cristobalite precipitation in composite ceramics could be controlled effectively by adjusting the heating rate, holding time, and sintering temperature. The sintering procedure is set as the heating rate of 4°C/min, sintering temperature of 1200°C, and holding time for 2 h, the flexural strength of SiO 2 –Al 2 O 3 composite ceramic is 47.13 MPa, dielectric constant ranges from 2.90 to 2.97, and the tangent of loss angle is less than 0.041. SiO 2 –Al 2 O 3 composite ceramics with high flexural strength and low dielectric constant were obtained by sintering procedure screening and optimization.
研究领域:
材料科学
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陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Gulizhabaier Abulipizi,Zimin Yu,Shaochen Lin,Nan Zhang,Fang Xu,Xin Wang,Zhanjun Li
Chromium-doped persistent luminescence nanoparticles (PLNPs) have promising biomedical applications in X-ray charged near-infrared (NIR) luminous imaging. The persistent luminescence (PersL) property was usually adjusted by co-doping with other ions. Impurity phases were thought to be adverse to the PersL. In this study, a composite material, LiInSi 2 O 6 :Cr,Pr·2SiO 2 (LICP-S), was synthesized with a PersL peak at 800 nm after being charged by 1 Gy X-ray while LiInSi 2 O 6 :Cr (LIC) and LiInSi 2 O 6 :Cr,Pr (LICP) possessed no or very weak PersL. Distinctively, excess metastable cristobalite silica was found essential for the much more intense PersL of LICP-S than LICP and LIC. Thermostimulated luminescence spectra studies indicated that cristobalite adjusted the Pr-related traps from deep traps to shallow ones, which facilitated the room temperature PersL. The low dose X-ray charged PersL of LICP-S was applied to demonstrate the luminous labeling of a medical silicone prosthesis that was supposed to be imbedded in body for years via X-ray activated PersL imaging in vitro and in vivo . This work not only provides a kind of PLNPs with 800 nm emission suitable for low dose X-ray activation, but also an unusual strategy for trap engineering in PersL materials by designing multi-phase composites.
研究领域:
材料科学
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生物医学工程
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医学影像学
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2025
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IF 5.6
Shuang Yin,Jiajun Liu,Chengyun Sun,Yao Zhang,Liqiang Liu,Ruzhong Zuo
In this study, high-performance fused silica ceramics were fabricated from bimodal distribution powders via gelcasting and pressureless sintering. The solid loading of slurries (60–85 vol%) and sintering conditions (1280 °C for 1–6 h) significantly influenced the composition, microstructure, sintering, and mechanical behavior of fused ceramics. Increasing solid loading promoted densification, enhanced bulk density, and inhibited cristobalite precipitation. In contrast, extending holding time enhanced viscous flow and densification, but increased cristobalite precipitation. Therefore, both solid loading and holding time must be optimized to enhance material densification and suppress cristobalite precipitation. Fused silica ceramics prepared under 80 vol% solid loading and 3 h holding time showed optimal overall performance. They achieved a bulk density of 2.00 g/cm 3 , a flexural strength of 71.21 MPa, and a linear thermal expansion coefficient (approximately 10 −6 /°C) within the range from room temperature to 1000 °C. Following 20 thermal shock cycles between room temperature and 1000 °C, the material retained a residual flexural strength of 23.64 MPa, with a corresponding strength retention rate of 33.20 %. This study provides valuable guidance for fabricating high-strength fused silica ceramics via gelcasting and pressureless sintering.
研究领域:
陶瓷工程
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材料科学
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微观结构调控
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力学性能
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热震性能
✓ 已验证
产品关联
DOI
高影响因子
CORROSION SCIENCE
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2020
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IF 6.479
Lian-Kui Wu,Jing-Jia Wu,Wei-Yao Wu,Hao-Jie Yan,Mei-Yan Jiang,Fa-He Cao
To improve the hot corrosion resistance, thickness controllable SiO 2 coating was electrodeposited on TiAl alloy. The hot corrosion behavior of the specimens contaminated with 75 wt.% Na 2 SO 4 + 25 wt.% NaCl salt mixture was investigated at 700 °C. Results showed that the generation of compact amorphous SiO 2 embedded with Na 2 Si 4 O 9 and cristobalite was responsible for the enhanced hot corrosion resistance. Moreover, the SiO 2 coating does not only act as a diffusion barrier to sulfur and chlorine but also decreases the oxygen partial pressure at the coating/alloy interface, therefore promoting the selective oxidation of Al to form protective Al 2 O 3 layer.
研究领域:
材料科学
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腐蚀工程
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2025
·
IF 5.6
Jiajun Liu,Shuang Yin,Chengyun Sun,Yao Zhang,Liqiang Liu,Ruzhong Zuo
Using the fused silica powders with unimodal distribution as raw materials, the 50 vol% slurries possessing outstanding flowability were prepared by optimizing slurries' pH value, fused silica's zeta potential, dispersant (acrylic acid-acrylamido-2-methypropane sulfonic acid copolymer) content, and ball milling time. Despite of high absolute value of ζ of powders under alkaline solution, the acidic and neutral solutions were more effective than alkaline solution in dispersing fused silica powders. When the AA-AMPS content and ball milling time were 1.2 wt% and 6 h, not only the powder agglomerates can be effectively opened, but also the AA-AMPS molecules can form a homogeneous monolayer adsorption state on the particle surface and generated strong electrostatic repulsion and steric hindrance effects. The enhancement of solid loading consumed more free water in slurries, simultaneously shortened particle distance and heightened particle collision or friction, thus impairing fluidity. The slurry exhibited a low viscosity of just 0.45Pa·s at 50 vol%, which can meet requirement of gelcasting. At a standing time of 120 h, the fused silica slurries still maintained good dispersion stability, with a volume sedimentation rate of only 2.89 %. For gelcasting-pressureless sintered fused silica ceramics, prolonged holding time at 1250 °C from 1 h to 6 h enhanced densification, but simultaneously promoted more detrimental cristobalite precipitation. The material achieved optimal performance at 3 h, exhibiting a bulk density of 1.89 g/cm 3 and flexural strength of 69.5 MPa. This work provides certain insights into preparing high-solid-loading, well-flowing aqueous fused silica slurries and high-performance fused silica ceramics.
研究领域:
材料科学
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陶瓷工程
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胶体与界面科学
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流变学
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粉末技术
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固体物理
✓ 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）