CERAMICS INTERNATIONAL
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2025
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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
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物理学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2021
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IF 9.229
Zhanxiang Yin,Zhongyuan Liu,Yuan Yu,Cunyin Zhang,Peng Chen,Jianxun Zhao,Pan He,Xin Guo
Polycrystalline BiCuSeO is considered as a promising thermoelectric material due to its intrinsically low thermal conductivity and moderate Seebeck coefficient. However, its low electrical conductivity and coupled electron–phonon transport properties restrict the further improvement of the thermoelectric performance. In this work, Pb and Yb dopants are incorporated into BiCuSeO to substitute for Bi sites via ball milling and high-pressure and high-temperature sintering, leading to a synergistic optimization of the electron and phonon transport and improved thermoelectric performance. The carrier concentration exhibits an enhancement with increasing Pb&Yb co-doping contents. Meanwhile, the decreased carrier mobility is suppressed appropriately by coordinating with the interplay of Pb and Yb dopants on the electronic structure. Besides, Pb&Yb co-doping combined with high-pressure and high-temperature sintering introduces abundant grain boundaries, dislocations, and point defects to effectively decrease the lattice thermal conductivity by scattering phonons in a broad frequency range. Coupled with the synergistic optimization of the electrical and thermal properties, a maximum zT of 1.2 is achieved in Bi0.88Pb0.06Yb0.06CuSeO at 850 K, which significantly outperforms the majority of oxygen-containing thermoelectric materials. Our study suggests that dual doping of bivalent ions and rare-earth elements at Bi sites is an effective strategy for improving the thermoelectric performance of BiCuSeO.
研究领域:
材料科学
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热电材料研究
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
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IF 6.371
Zihao Yin,Jingyun Chen,Zhenbo Qin,Yingjun Wang,Zhong Wu
We developed a layered composite with directional distributed reduced graphene oxide (RGO) in a copper matrix through a double-slot multi-step electrodeposition method, playing to the advantage of in-plane thermal conductivity of RGO. The resulting RGO/Cu composite has superior thermal conductivity up to 545 W m −1 K −1 (150% of copper), which was determined by the growth behavior of the RGO flake on the copper substrate through adjusting electrodeposition time. By analyzing the structure, distribution status and its relationship with thermal conductivity, three factors including of structural integrity of RGO, thermal conduction network and interfacial effect between RGO layers were proposed. With the increase of deposition time, the restoration of RGO lattice structure and the formation of a complete thermal conduction network both promoted the phonon transmission, which was beneficial to the improvement of thermal conductivity. The multi-layer stacking of RGO, however, could generate the interlayer interfacial effects, resulting in the phonon scattering and unfavorable to the thermal conductivity. Therefore, proper adjustment of RGO deposition time resulted in excellent thermal conductivity of RGO/Cu composite, meeting the demands for the heat dissipation performance of the instrument.
研究领域:
材料科学
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热工程
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
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2025
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IF 14.2
Peiwen Yang,Weijie Kong,Bo Li,Siyun Liang,Yuchen Qu,Peiluo Shi,Gang Li,Xiaoping Yang
The construction of thermally conductive interphase without sacrificing interfacial properties remains challenging for the fabrication of high-performance carbon fiber-reinforced polymer (CFRP) composites. In this work, one-dimensional clavate liquid crystalline polymer (1D C-LCP) and two-dimensional discotic liquid crystalline polymer (2D D-LCP) were synthesized and applied to construct structural-functional interphase in M40X carbon fiber/epoxy (CF/EP) composite, and the correlations of the LCP dimensionality with thermal conductive and interfacial performance were experimentally analyzed and molecularly simulated. The smectic C-LCP and columnar D-LCP improved the surface roughness and chemical activity of M40X CF. Compared to pristine CF/EP composites, the experimental out-of-plane and simulated interfacial thermal resistance of C-LCP-CF/EP and D-LCP-CF/EP composite were respectively alleviated by 45.1 %, 32.2 % and 53.1 %, 52.9 % due to the construction of unidirectional and multichannel thermal conductive pathways at the interphase. The dominant in-plane vibration mode facilitated the parallel phonon transmission, which led to the 163.2 % and 85.8 % improvement in interfacial phonon coupling and interfacial interaction energy of C-LCP-CF/EP composite. Comparatively, the multi-directional phonon transport channels were established by the synergy of out-of-plane and in-plane vibration mode, which induced 26.7 % and 77.5 % increase in interfacial phonon coupling and π-electron accumulation density, leading to the highest thermal conductive and interfacial performance of D-LCP-CF/EP composite.
研究领域:
材料科学
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高分子科学
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纳米技术
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热工学
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计算化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2023
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IF 6.1
Ning Jia,Bin Yang,Xiaohong Wang,Shishuang Cui,Peng Chen,Ru Xia,Zhengzhi Zheng,Jiasheng Qian,Yuchao Ke,Yang Pan
In this study, graphene nanoplatelets (GNP) and nickel–cobalt (NiCo) alloy were adopted as reinforcing materials to prepare epoxy (EP) resin-based composites. NiCo particles were able to achieve uniform anchoring on GNPs’ surface under the electrostatic force due to the successful introduction of oxygen defects on GNPs. With the synergistic effect of adhesive PVDF and salt particles, the system with three-dimensionally (3D) interconnected network was successfully constructed. Benefit from the formation of mechanically stable and efficient heat conduction paths, the thermal conductivity (TC) of the EP/PVDF/NiCo@GNP composite reached 1.077 W⋅m −1 ⋅K −1 at a filler volume fraction of 6.82 vol%, while the counterpart’s storage modulus ( E’ ) was up to 3.22 GPa. In addition, a scaling formula was quantitatively proposed to correlate TC with E’ , and the perfect agreement between the theoretical prediction and experimental data clarified the underlying mechanism of the relationship between phonons transport and stress transfer within a system with 3D ordered structures. The establishment of relationship between AHR (average heating rate) and TC made it possible to further predict TC of composites based upon the infrared thermal imaging (ITI) data. The as-prepared GNP composites show good application prospects as thermal management materials which need to experience thermally mechanical deformation.
研究领域:
材料科学
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复合材料
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热管理
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纳米技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）