CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Wenyi Li,Feng Li,Xiaoming Qiu,Chuangchuang Gong,Min Jiang,Zhenxin Zhao,Xiaomin Wang
Owing to the intrinsic dielectric-magnetic coupling loss mechanism, perovskite-type lanthanide-transition metal oxide (LaTMO 3 ) is considered as a promising candidate for electromagnetic wave absorbing material, but unmodified LaTMO 3 suffers from limited polarization processes and weak super-exchange magnetic response. Herein, we manipulate the TM-O bond properties by regulating the configuration entropy of transition metal sites to address such issues within single-phase LaTMO 3 . Elaborate structural characterization and P-V-L bond theory demonstrate quantitatively the optimization of electromagnetic wave absorption performance mainly stems from the synergistic improvement in TM-O bond distortion degree and covalency, as well as the formation of diverse super-exchange pathways. Consequently, the high entropy La(Cr 0.2 Mn 0.2 Fe 0.2 Co 0.2 Ni 0.2 )O 3 exhibits a minimum reflection loss of −50.68 dB, an effective absorption bandwidth covering entire Ku band of 7.6 GHz. The radar cross section of the structure with La(Cr 0.2 Mn 0.2 Fa 0.2 Co 0.2 Ni 0.2 )O 3 coating are less than −10 dBm 2 within the incident angles -60-60°. This study contributes to a deeper understanding of design and preparation of efficient broadband electromagnetic wave absorbing materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Jiacheng Cao,Min Zhu,Xuefeng Lu,Faqi Zhan,Yuehong Zheng,Peiqing La
One of the key strategies for enhancing the thermoelectric figure of merit (ZT) is the simultaneous optimization of electron and phonon transport. In this work, (Sr 0.25 Ba 0.25 La 0.25 Pb 0.25 ) 1-x Nb 2 O 6-δ (0 ≤ x ≤ 0.15) ceramics were synthesized via the solid-state reaction method. By introducing a series of A-site defects into the high-entropy system, configurational entropy was modulated to optimize thermoelectric performance. As the value of x increased, both electrical resistivity and thermal conductivity exhibited significant reductions. Due to the synergistic effect of relatively high power factor (PF) and low thermal conductivity (κ), the sample with x = 0.1 achieved a peak ZT value of 0.19 at 1073 K, representing a 137.5 % enhancement over the stoichiometric ceramic sample. This research demonstrates that in the distorted tetragonal tungsten bronze structure, enhanced crystal symmetry facilitates electron delocalization, thereby improving electrical transport properties. Additionally, defects, including edge dislocations confirmed by scanning transmission electron microscopy analysis, increase the likelihood of random scattering events, leading to a reduction in lattice thermal conductivity. This study demonstrates that in (Sr 0.25 Ba 0.25 La 0.25 Pb 0.25 )Nb 2 O 6−δ high-entropy ceramics, the synergistic modulation of A-site defect concentration and configurational entropy effectively optimizes electron and phonon transport properties , thereby achieving a peak ZT value of 0.19.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Jinxu Ma,Kepi Chen,Cuiwei Li,Xiaowen Zhang,Linan An
The valence-combination strategy was applied to design B-site substitution non-equimolar stoichiometric high-entropy perovskite oxides (HEPOs). 29, 56 and 29 valence combinations with the maximum configurational entropy higher than 1.5R for five-component HEPOs were identified when the average valence of B-site is 3, 4 and 5, respectively. Synthesis experiment was performed on 8 valence combinations with the average valence of B-site equal to 4. Single-phase HEPOs were obtained from 6 of them. It was also found that most of HEPOs have ordered structures. The formation of single-phase HEPO and ordered structure was discussed in terms of structural tolerance factor and valence-difference factor.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
iScience
·
2025
·
IF 4.1
Qingqing Cai,Rui Xu,Tao Wang,Lengyuan Niu,Yinyan Gong,Can Li
Medium-entropy compounds (MECs) have attracted significant interest thanks to their exceptional mechanical, physical and chemical properties, which are associated with their unique atomic structures. In this study, we enhanced the performance of MECs by optimizing their configurational entropy, leading to the formation of abundant quantum dots (QDs) and improved catalytic activity. This structural optimization not only adjusted electronic properties but also boosted catalytic performance and stability in oxygen evolution reactions (OER). MEC-Fe 2.0 catalyst demonstrated a low overpotential and outstanding long-term stability compared to others. Density functional theory simulations revealed that the incorporation of Co and Ni atoms increased the configurational entropy and facilitated the formation of short-range ordered QDs. This modification effectively lowered the chemical activity of Fe site, contributing to the enhanced catalytic performance. This design approach provides a promising strategy for advancing MEC, offering a pathway to improve their catalytic efficiency for various applications.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2025
·Vol. 108
·期 5
·e20355
·
IF 3.8
Liang Xu,Hongfei Gao,Xin He,Min Niu,Zhiwei Dai,Haotian Ni,Lei Su,Hongjie Wang
Ceramic thermal barrier coating (TBC) materials are used to protect the superalloys from the damage of harmful high-temperature airflow and improve the efficiency of jet and gas turbine engines. However, the long-term application of TBC materials and the robustness of these materials can be destroyed by aggressive calcium-magnesium-alumina-silicate (CMAS) melt during high-temperature service. Increasing the configuration entropy of material by doping multiple principal components has become a research hotspot in the design of corrosion-resistant thermal barrier coating material and has opened an infinite space of chemical composition, structure, and material properties. In this study, high-entropy (La 0.2 Sm 0.2 Er 0.2 Y 0.2 Yb 0.2 ) 2 Ce 2 O 7 was synthesized and its CMAS corrosion behavior was investigated by experimental investigation and first-principles calculation. The effects of the increase of configurational entropy and the subsequent potential effects on the CMAS corrosion behavior of Ce-based fluorite oxides have been sufficiently investigated. By compared with control samples, the high-entropy (La 0.2 Sm 0.2 Er 0.2 Y 0.2 Yb 0.2 ) 2 Ce 2 O 7 possesses the minimum infiltration depth of CMAS melts and the denser corrosion reaction layer, indicating the best corrosion resistance. The corrosion resistance mechanism of high-entropy (La 0.2 Sm 0.2 Er 0.2 Y 0.2 Yb 0.2 ) 2 Ce 2 O 7 was studied by first-principles calculation. The greater stability and resistance to segregation of CMAS melt in the CMAS/(La 0.2 Sm 0.2 Er 0.2 Y 0.2 Yb 0.2 ) 2 Ce 2 O 7 system, the poor adsorption capacity for CMAS melt which leads to a weak infiltration ability of CMAS melt; the weakest interfacial chemical reaction at the interface indicated by the smallest value of Griffith rupture work and the least species migration of high-entropy fluorite oxide can be responsible to the enhanced corrosion resistance. Our work reveals that increasing the configuration entropy can be an effective strategy for TBC material to enhance corrosion resistance.
研究领域:
材料科学
·
计算材料学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2025
·
IF 9.5
Chenyang Duan,Hao Zhang,Zhiwei Hu,Zhenya Li,Wenjie Bian,Chao Jing,Jian-Qiang Wang,Linjuan Zhang
Modulating the configurational entropy of materials is an effective strategy to develop efficient and robust electrocatalysts for the oxygen evolution reaction (OER) in clean energy technologies. However, the impact of configurational entropy on catalytic activity has received limited attention. In this study, we systematically investigate a class of alloy catalysts composed of Cr, Mn, Fe, Co, and Ni, as a function of Ni content to modulate the configurational entropy to 1.50R (high-entropy alloy, Ni-HEA), 1.23R (medium-entropy alloy, Ni-MEA), and 0.66R (low-entropy alloy, Ni-LEA), where R is 8.314 J (mol−1 K−1). In situ Raman spectroscopy reveals that increased configurational entropy facilitates the formation of the OER active γ-NiOOH phase on the alloy surface. This transition leads to a significant decrease in the OER overpotentials and Tafel slopes. The optimized Ni-HEA exhibits an overpotential of only 217 mV at 10 mA cm−2, and demonstrates prolonged operational stability for 600 hours under industrial conditions. This work enhances our understanding of the impact of configurational entropy on catalytic activity and offers a novel approach for the rational design of porous high-entropy catalysts with improved OER efficiency.
研究领域:
材料科学
·
电化学
·
清洁能源技术
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2022
·Vol. 13
·期 1
·1-12
·
IF 17.694
Fu Fang,Liu Xiang,Fu Xiaoguang,Chen Hongwei,Huang Ling,Fan Jingjing,Le Jiabo,Wang Qiuxiang,Yang Weihua,Ren Yang,Amine Khalil,Sun Shi-Gang,Xu Gui-Liang
P2-type sodium manganese-rich layered oxides are promising cathode candidates for sodium-based batteries because of their appealing cost-effective and capacity features. However, the structural distortion and cationic rearrangement induced by irreversible phase transition and anionic redox reaction at high cell voltage (i.e., >4.0 V) cause sluggish Na-ion kinetics and severe capacity decay. To circumvent these issues, here, we report a strategy to develop P2-type layered cathodes via configurational entropy and ion-diffusion structural tuning. In situ synchrotron X-ray diffraction combined with electrochemical kinetic tests and microstructural characterizations reveal that the entropy-tuned Na 0.62 Mn 0.67 Ni 0.23 Cu 0.05 Mg 0.07 Ti 0.01 O 2 (CuMgTi-571) cathode possesses more {010} active facet, improved structural and thermal stability and faster anionic redox kinetics compared to Na 0.62 Mn 0.67 Ni 0.37 O 2 . When tested in combination with a Na metal anode and a non-aqueous NaClO 4 -based electrolyte solution in coin cell configuration, the CuMgTi-571-based positive electrode enables an 87% capacity retention after 500 cycles at 120 mA g −1 and about 75% capacity retention after 2000 cycles at 1.2 A g −1 .
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2023
·
IF 5.7
Xiaohui Tang,Hongjun Zhang,Fangzhe Li,Dongliang Wang,Yong Huang,Hua Ke
Dielectric capacitors play an increasingly important role in power systems because of their fast charging and discharging speed. Applications are usually limited due to the low W rec . We design materials with high values of Δ P ( P max - P r ) and recoverable energy storage density( W rec ) from the high entropy perspective. Two single phases with a large Curie temperature T c difference have been selected, which leads to the enlarged entropy. The ceramics (Bi 0.85 Nd 0.1 Sm 0.05 ) 1- x Ba x )(Fe 1- x Ti x )O 3 (BNSBFT x ) are prepared by the solid-state reaction. As x increases, the corresponding configuration entropy( S config ) goes from 1.4 R to 1.52 R. The increased entropy destroys the long-range order, accompanied by the reduced remanent polarization( P r ) and the improved W rec . The W rec of BNSBFT 0.5 ceramics reaches 4.9 J/cm 3 at a low field of 250 kV/cm. Both temperature change(∼ 0.5% from 30 °C to 140 °C) and frequency variation(∼ 4.8% from 1 Hz∼50 Hz) in W rec show excellent stability.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Zhemin Chen,Yongping Pu,Yating Ning,Chunhui Wu,Lei Zhang,Bo Wang,Xuqing Zhang
Eco-friendly dielectric ceramics with excellent energy storage performance and dielectric temperature stability are the kernel parts of pulsed power devices in the next-generation. However, the contradiction between high breakdown electric field ( E b )and maximum polarization ( P max ) restricts the improvement of comprehensive performance. Herein, we report a novel strategy of entropy engineering in the superparaelectric state to address the above concerns. On the one hand, near-linear polarization response can be achieved in the superparaelectric state, which can be beneficial to obtain a large P max , low remnant polarization ( P r ) and slim P-E loops. On the other hand, the improvement of configuration entropy (Δ S config ) is conducive to refining grain size and domain size, enhancing bandgap width, and suppressing leakage current and interfacial polarization, thus the generation of large E b . Therefore, with the Δ S config increases from 0.98 R to 1.44 R, a giant energy storage density ( W rec ) of 8.11 J/cm 3 as well as a high efficiency ( η ) of 90.2 % are synchronously obtained. Significantly, the optimum sample shows outstanding dielectric temperature stability (Δ C / C 25°C ≤ ± 15 %, −55 ∼ 165 °C) in accordance with X8R. This work demonstrates that the medium entropy superparaelectrics are a shortcut to achieve next-generation ceramic capacitors with high comprehensive performance.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）