JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
·
IF 5.8
Chufei Cheng,Ruixin Hao,Jiadong Hou,Fengnian Zhang,Fuhao Cheng,Ziqian Meng,Bei Ren,Yang Miao,Libiao Xin,Xiaomin Wang
In the thermal protection system of spacecraft, the bolts connecting the ceramic to the internal superalloy need to have low thermal conductivity and high strength . Two dense high entropy fluorite oxides (Zr 1/7 Hf 1/7 Ce 1/7 Y 2/7 La 2/7 )O 2-δ (ZHCYL) and (Zr 1/8 Hf 1/8 Ce 1/8 Y 1/4 La 1/4 Pr 1/8 )O 2-δ (ZHCYLP) were designed and synthesized by using the synergistic effect of plasma-assisted ball milling and spark plasma sintering(SPS). Through the synergistic effect of lattice distortion and oxygen vacancy guided by entropy regulation, ZHCYLP synthesized in this study has lower thermal conductivity(1.13 W·m −1 ·K −1 ), higher high temperature strength(192 MPa at 1000 °C) and high temperature phase stability up to 1600 °C than 8YSZ ceramics. The thermo-mechanical coupling finite element analysis results of high temperature bending test show that the variation trend of the maximum stress value of the sample is consistent with the experimental results. This shows that the mechanical and thermal properties of high entropy oxides can predict the variation trend of the maximum stress value in high temperature bending tests. It opens up a new way for designing and synthesizing high entropy oxide materials with low thermal conductivity and high strength which can be applied in the field of heat protection and load bearing.
研究领域:
材料科学
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航天工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2025
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IF 7.2
Haiying Xin,Liyan Xue,Mengtong Ma,Ke Song,Qiyong Deng,Zhiyi Wang,Minzhong Huang,Fan Yang
To mitigate the urban heat island effect, align with the “double carbon strategy”, and address the issues of coating aging and mildew on building facades, multifunctional ternary entropy-regulatory tungstate ceramic cool pigments (Ce x Ho 0.1 Gd 1.9– x W 2 O 9+ δ ) were prepared by high-temperature solid-phase method in this study. While ensuring the high near-infrared (NIR) solar reflectance, the anti-ultraviolet (UV) aging and antimycotic performance of rare earth given to pigment were evaluated, and its optical properties, microstructure and practical application effects were deeply explored. The results indicate that ternary entropy regulation changes the color of the pigment from white to yellow, significantly reducing the band gap from 3.28 to 1.90–1.87 eV. Specifically, the Ce 0.2 Ho 0.1 Gd 1.7 W 2 O 9+ δ pigment exhibits excellent chromatic properties ( L * = 73.79, a * = 20.21 and C * = 50.51) and a high NIR solar reflectance (96.23%). Infrared thermography confirms that it has a good cooling effect, with temperatures of 3.5 °C lower than the commercially available coating of similar color. Furthermore, the performance of multifunctional integration is that the pigments show enhanced absorption in the UVA (long-wave ultraviolet 320–400 nm) range, with an increase in average light absorption from 0.19 to 0.91 and a substantial increase in antimycotic rate from 42.86% to 97.46%. At the same time, this material has good acid and alkali resistance (Δ E * ≤ 2.41). The successful development of the multifunctional cool pigment materials opens a new way to energy-saving architectural wall coating materials.
研究领域:
材料科学
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建筑节能
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
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IF 8.128
Chenbo Meng,Kexiong Gao,Siyi Tang,Linsen Zhou,Wenchuan Lai,Longbo Luo,Xu Wang,Yang Liu,Ke Wang,Yue Chen,Xiangyang Liu
Aromatic macromolecules tend to form a compact conformation after physically adsorbed on graphene and it brings about great entropy loss for physisorption , due to the strong interaction between aromatic macromolecules and graphene. However, previous researches have validated the availability of aromatic macromolecules to stabilize graphene based on physisorption. In order to clarify the underlying mechanism of this physisorption process on graphene, a series of aromatic polyamide copolymers are used as models in this research. Apart from their adsorbed conformations on graphene, the conformations of these copolymers as the free states in diluted solutions are taken into consideration. Although these copolymers present the fully extended conformation on graphene, their conformations in diluted solutions vary largely with the copolymer composition . It is verified that the copolymer with smaller conformational change could have the better stabilization effectiveness for graphene, rather than the one having stronger interaction with graphene. Therefore, the entropy-tailored behavior for the adsorption of aromatic macromolecules on graphene is put forward. Based on this mechanism, the chemical structure of aromatic polyamide is optimized and furthermore it is utilized to directly exfoliate natural graphite flakes. Eventually, high-quality graphene nanosheets with a large dimension and low defects are obtained. Moreover, its exfoliating effectiveness is superior to those of the commonly used exfoliating agents nowadays.
研究领域:
材料科学
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物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2023
·Vol. 11
·期 37
·19955-19964
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IF 11.9
Yusong Wang,Yingshuai Wang,Yuhang Xing,Chunyu Jiang,Yanfei Pang,Hongfeng Liu,Feng Wu,Hongcai Gao
P2-type Na0.67Ni0.33Mn0.67O2 is a promising cathode for sodium-ion batteries due to its high theoretical capacity, facile fabrication, low cost, and environmental friendliness. However, it suffers from an undesirable phase transformation and severe capacity fading above 4.2 V. In this work, we propose a strategy to improve the performance of the P2-type layered transition metal oxide cathode by adjusting the configurational entropy of the material and the synergistic effect of zinc and magnesium co-doping. We use X-ray diffraction (XRD), X-ray photoelectron spectroscopy, and in situ XRD technologies to reveal the change in configurational entropy of the material structure and to explore the influence of related factors. The structural and thermal stability was improved through modification with zinc and magnesium co-doping, compared to Na0.67Mn0.67Ni0.37O2. Meanwhile, the P2 to O2 phase transition of the material under high voltage was inhibited. When tested in combination with a sodium-metal anode in a coin cell configuration, Na0.67Mn0.67Ni0.21Mg0.06Zn0.06O2 exhibited improved rate capability (69.24 mA h g−1 at 10C) and excellent cycling stability (82.1% capacity retention after 200 cycles at 1C). This work presents a route to rationally design cathode materials with entropy modulation to improve the performance of cathode materials for sodium-ion batteries.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2025
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IF 19
He Liu,Ke-Feng Ren,Yun-Fei Du,Jia-Xin Guo,Zhong-Yu Li,Zhen-Hui Luo,Xin Sun,Cong Guo,Weizhai Bao,Feng Yu,Xin Shen,Xin-Bing Cheng,Jingfa Li
The concept of high entropy is applied to various rechargeable batteries to improve the thermodynamic and kinetic behavior of electrolytes. However, the quantization and functionality of entropy are still ambiguous in liquid electrolytes. Herein, the regulation of entropy in non-aqueous electrolytes is quantitatively understood to construct robust Li metal batteries. Electrolyte entropy is first quantified through combining the Boltzmann statistical mechanics with the statistics of solvation structure configurations in the non-aqueous electrolyte. Entropy values do not necessarily increase with the increasing electrolyte components. Electrolytes with higher entropy dissociate ion aggregation to form homogeneous solvation structures, which effectively balance strong/weak solvation effects. This induces smaller cluster size, accelerating diffusion kinetics and desolvation process of Li + . An average Coulombic efficiency of 99.1% is obtained in Li||Cu batteries. Li||LiNi 0.5 Co 0.2 Mn 0.3 O 2 cells with a high cathode loading (19.7 mg cm −2 , 3.0 mAh cm −2 ) can maintain a capacity retention of 87.1% after 200 cycles. This finding offers novel understandings in the role of high-entropy effect, which is of great importance for the development of high-energy-density Li metal batteries.
研究领域:
电化学
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储能
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材料科学
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物理化学
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电池技术
✓ 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）