Advanced Composites and Hybrid Materials
·
2018
·Vol. 1
·期 3
·548-557
·
IF 0
Mao Fan,Shi Zhicheng,Wang Jing,Zhang Chao,Yang Chaoqiang,Huang Minghua
The search for high-performance dielectric materials has long been driven by the urgent needs for various modern electronics. However, enhanced permittivity is always accompanied by elevated loss, which seriously hinders the development and applications of dielectric materials. Herein, negative- k layers were introduced into layer-structured films, forming a new class of multilayer composites consisting of alternately stacked positive- k and negative- k layers. Compared with traditional multilayer composites without negative- k layers, the layered composites containing extra positive- k /negative- k interfaces exhibit superior ability in balancing the contradict parameters: permittivity and loss, yielding substantially enhanced permittivity without sacrificing the low loss. It is indicated that the permittivity was enhanced by the charge accumulations and reinforced polarizations on the interfaces between positive- k and negative- k layers. Meanwhile, the loss induced by the leakage current was suppressed by the blocked transport of carriers between adjacent layers. The trilayered 60-3.5-60 composite exhibits an enhanced dielectric constant ( ε ′ ≈ 33 @10 kHz) and retained low loss (tanδ ≈ 0.12 @10 kHz) compared with the single-layer BT/PVA composite containing 60 wt% BT fillers ( ε ′ ≈ 9.5 @10 kHz, tanδ ≈ 0.075 @10 kHz). This research offers an effective way to design and fabricate novel high-performance dielectric materials.
Improved dielectric permittivity and retained low loss were obtained in layer-structured films via adjusting interfaces.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 7
·1-8
·
IF 2.8
Xu Tao,Liu Huiping,Zhao Rongjun,Yuan Linjie,Zhu Zewei,Chen Xi,Hou Haoqin,Peng Xinwen
Polymer film capacitors do not meet the increasing demand of high-temperature (> 125 °C) applications with the rapid development of new energy. In particular, few polymer dielectrics can operate at high temperatures (> 250 °C). In order to develop high-temperature-resistant polymer dielectrics, a novel polyimide containing porphyrin units (PI-a) was prepared by using this diamine polymerized with 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BTDA). PI-a possesses high dielectric constant up to 9.04; however, its highly rigid backbone and low molecular weight affect other properties and applications. Here, high-performance polyimide dielectrics were developed by a highly scalable and low-cost strategy. The PI-a and PI-b which was prepared with 4,4′-diaminodiphenyl ether (ODA) and BTDA are mixed by proper design to improve dipolar polarization and intermolecular interactions among polymer chains. Consequently, such polyimide blend with the ratio of PI-a 40% displays an intrinsic giant permittivity of 6.68, low dielectric loss (< 0.05), the highest energy storage density (2.87 J cm −3 ), and possesses excellent mechanical property and excellent thermal stability. These obtained polyimide blends can extend applications of film capacitors at high temperature.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2013
·
IF 3.328
Xinzhou Wu,Zheng Chen,Zheng Cui
Albumen and BaTiO 3 nanoparticles are employed to make solution processable nanocomposite for high permittivity films. The nanoparticles are modified with poly(acrylic acid) molecules to achieve homogeneous dispersion in albumen aqueous solution and made into films by drop casting. The dielectric constant and loss tangent of albumen–BaTiO 3 nanocomposites are investigated as the function of volume fraction of BaTiO 3 . The nanocomposites exhibit maximum relative permittivity of 52 and good dielectric stability over a wide range of frequency, while the loss tangent is below 0.05 even at high BaTiO 3 loading of 80 vol%. The dielectric constants of nanocomposites with lower volume fractions (<41 vol%) are in good agreement with the Lichtenecker-Logarithmic model.
研究领域:
材料科学
·
生物材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Guohua Fan,Xiaoping Zhang,Qingyu Wang,Ran Su,Yanan Tang,Chuncheng Hao,Yao Liu
Ceramic composites made up of well-selected components have enriched the varieties of the metamaterials with negative electromagnetic parameters. In this work, TiN/BaTiO 3 ceramic composites were prepared with a simple dry-pressing and pressureless sintering process. Percolation was eventually determined to be the key inducements which caused the permittivity of the ceramic composites changing from positive to negative. Essentially, negative permittivity was closely related to the plasma oscillations of free electrons in percolation networks. Meanwhile, conduction mechanism of the composites varied owing to the changes in microstructure, where the percolation networks brought out pathways for electron migration and achieved high conductivity. In addition, ac impedance behavior with changes of the sign for reactance were also discussed, thus the transition from electrical capacitive to inductive for the percolative ceramic composites has been demonstrated. This work clarified the influence of percolation on the conductivity, impedance, and permittivity of ceramic composites altogether. The obtained negative permittivity composites have enormous potential in various electronic devices and electromagnetic apparatus.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Ruolin Han,Jiafei Ren,Zheng Zhou,Guang-Xin Chen,Qifang Li
Typically, the basic method to enhance the dielectric response of polymer-based composites is to fill giant dielectric ceramic fillers, such as BaTiO3 and CaCu3Ti4O12, into the polymer matrix. Here, by using low-k boron nitride (BN) with well-controlled microstructure and surface, we successfully prepared a high-k polymeric composite, where the improvement in the dielectric constant of the composite even exceeds that of composites containing BaTiO3 and CaCu3Ti4O12 particles at the same weight percent. First, a lamellar boron nitride nanosheet (BNNS) aerogel was prepared by bidirectional freezing and freeze drying, respectively, and then the aerogel was calcined at 1000 °C to obtain the lamellar BNNS skeleton with some hydroxyl groups. Finally, the epoxy resin (EP) was vacuum impregnated into the BNNS skeleton and cured inside to prepare the lamellar-structured BNNSs/EP (LBE) composites. Interestingly, the dielectric constants of LBE with a 10 wt % BNNS content reached 8.5 at 103 Hz, which was higher by 2.7 times than that of pure EP. The experimental data and the finite element simulations suggested that the increased dielectric constants of LBE resulted from the combination of two factors, namely, the lamellar microstructure and the hydroxyl groups. The stacking of the BNNS phase into a highly connected lamellar skeleton significantly increased the internal electric field and the polarization intensity, while the introduction of hydroxyl groups on the BNNS surface further improved the polarization of the composite, resulting in a significant increase in the dielectric constant of the LBE. This work provides a new strategy for improving the dielectric constant through the microstructure design of composites.
研究领域:
材料科学
·
复合材料
·
介电材料
·
聚合物科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2021
·Vol. 13
·期 20
·3489
·
IF 4.329
Yashu He,Jingting Wang,Igor S. Sirotin,Vyacheslav V. Kireev,Jianxin Mu
This study reports on a series of crosslinked poly(arylene ether)s with POSS in the main chain. The fluorinated and terminated poly(arylene ether)s were first synthesized by the nucleophilic reaction of diphenol POSS and decafluorodiphenyl monomers, including decafluorobiphenyl, decaflurobenzophenone, and decafluorodiphenyl sulfone. They were then reacted with 3-hydroxyphenyl acetylene to produce phenylacetylene-terminated poly(arylene ether)s. The polymers were of excellent processability. When heated to a high temperature, the polymers converted into a crosslinked network, exhibiting a low range of dielectric constant from 2.17 to 2.58 at 1 HMz, strong resistance against chemical solutions, low dielectric losses, and good thermal and hydrophobic properties.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2022
·Vol. 16
·期 6
·996-1002
·
IF 4.803
Zhang Changgeng,Zhang Qi
Recent advances in novel electroactive devices have placed new requirements on material development. High-performance dielectric elastomers with good mechanical stretchability and high dielectric constant are under high demand. However, the current strategy for fabricating these materials suffers from high cost or low thermal stability, which greatly hinders large-scale industrial production. Herein, we have successfully developed a novel strategy for improving the dielectric constant of polymeric elastomers via deep eutectic solvent inclusion by taking advantage of the low cost, convenient and environmentally benign synthesis process and high ionic conductivity from deep eutectic solvents. The as-prepared composite elastomers showed good stretchability and a greatly enhanced dielectric constant with a negligible increase in dielectric dissipation. Moreover, we have proven the universality of our strategy by using different types of deep eutectic solvents. It is believed that low-cost, easy-synthesis and environmentally friendly deep eutectic solvents including composite elastomers are highly suitable for large-scale industrial production and can greatly broaden the application fields of dielectric elastomers.
研究领域:
材料科学
·
电活性设备
·
聚合物科学
✓ 已验证
DOI
高影响因子
MACROMOLECULES
·
2019
·
IF 5.997
Chao Qian,Runxin Bei,Tianwen Zhu,Weiwen Zheng,Siwei Liu,Zhenguo Chi,Matthew. P. Aldred,Xudong Chen,Yi Zhang,Jiarui Xu
An original design strategy for the preparation of polymers with a low dielectric constant is presented. The key to this design strategy is taking the most advantage of the secondary relaxation behavior of the polymer chains to obtain more free volume in the bulk, which can effectively reduce the dielectric constant of the polymer. By using this design strategy, we have successfully synthesized a novel polyimide TmBPHF with a pendant group that consists of a biphenyl unit attached to the meta-position of a phenyl ring that is part of a triaryl unit. The intrinsic k and dielectric loss values of the TmBPHF are 2.09 and 0.0012 at 10 kHz, respectively. More importantly, such outstanding low-k performance remains stable up to 300 °C. The excellent low-k performance of TmBPHF is mainly due to the secondary relaxation, especially the β relaxation, which occurs from the rotation of the pendant group. The TmBPHF film shows an ultralow moisture rate (∼0.17%), which is able to maintain the low-k property stability in different humid environments. Meanwhile, the TmBPHF film also shows excellent thermal stability and excellent mechanical properties, with a glass transition temperature (Tg) of 302 °C, 5 wt % decomposition temperature (Td5%) of 549 °C, and residual of 70% at 800 °C under N2. The tensile strength and tensile modulus of the polyimide film are equal to 85.8 MPa and 2.02 GPa, respectively. In addition, the TmBPHF film is soluble in common solvents, which allows simple solution processing and efficient, low-cost, and continuous roll-to-roll processes. The design strategy is beneficial for lowering the k value and simultaneously maintaining the overall properties of polyimides, which possibly could also be extended to other novel high-performance polymer systems.
研究领域:
材料科学
·
高分子化学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
Crystals
·
2023
·Vol. 13
·期 7
·1140
·
IF 2.7
Jiuyuan Han,Mengjiao Chi,Liu Yang,Bing Liu,Minmin Mao,Hadi Barzegar Bafrooei,Zhongyan Ma,Yingjie Ren,Feng Shi,Ehsan Taheri-Nassaj,Dawei Wang,Kaixin Song
In this study, dense composites of xNaCl-(1−x)Ni0.5Zn0.5Fe2O4(referred to as NaCl-NZO) and xH3BO3-(0.8−x)Ni0.5Zn0.5Fe2O4-0.2NaCl (referred to as HB-NZO-NaCl) were prepared using the cold sintering process. The objective was to investigate the cold sintering procedure for fabricating ferrite composite ceramics with comparable permeability and dielectric constants suitable for radio-frequency electronic device applications. Optimal cold sintering conditions were determined as 200 °C/30 min/500 MPa with a relative density of 95% for NaCl-NZO and 120 °C/30 min/300 MPa with a relative density of 95.4% for HB-NZO-NaCl. X-ray diffraction and scanning electron microscope analyses confirmed the absence of secondary phases. The resulting composite ceramics showed promising characteristics, with the 0.5NaCl-0.5NZO composition exhibiting a dielectric constant of 6.2 @ 100 MHz, dielectric loss of 0.02 @ 100 MHz, permeability of 2.5 @ 100 MHz, and magnetic loss of 0.001 @ 100 MHz. Similarly, the 0.3HB-0.5NZO-0.2NaCl composition displayed a dielectric constant of 5.9 @ 100 MHz, dielectric loss of 0.02 @ 100 MHz, permeability of 5.1 @ 100 MHz, and magnetic loss of 5 × 10−4@ 100 MHz. These findings indicate potential applications in wireless communication.Keywords:cold sintering;magnetic–dielectric materials;ferrite;dielectric constant
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
Polymers
·
2019
·Vol. 11
·期 3
·526
·
IF 3.164
Jiayun Chen,Xiaoying Xiong,Qilong Zhang,Lingling Shui,Shitao Shen,Hui Yang,Zhicai Zhu,Fang Zhang
P(VDF-TrFE) (vinylidene fluoride-co-trifluoroethylene)/PMMA (PVT/PMMA) blended films synthesized through a facile solution-blending method show outstanding performance for practical electrowetting and energy storage applications. The van der Waals forces and dipolar interactions in neighboring P(VDF-TrFE) and PMMA chains, together with the suppressed free volume (or defect) are critical to the significantly-enhanced electrical properties. Typical, Teflon-covered P(VDF-TrFE)/PMMA blended film exhibits a high dielectric constant of 13 with low dielectric loss (~0.05) at 100 Hz and a large initial contact angle of 122°. Its electrowetting response with a contact angle modulation of 50° in air and low contact angle hysteresis demonstrate that it is promising for low-voltage electrowetting applications. Furthermore, with an energy density of 11.8 J/cm3, approximately double that of pure P(VDF-TrFE), PVT/PMMA blended films containing 20 wt % PMMA turn out to be superior materials for energy storage applications, due to their significantly-enhanced polarization and reduced remnant polarization.Keywords:electrowetting;energy storage;dielectric constant;hydrophobicity
研究领域:
材料科学
·
电气工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2022
·Vol. 51
·期 12
·6964-6974
·
IF 2.047
Geng Zhibin,Liu Hong,Xiong Wei
Polymer/conductor composites are used in energy storage capacitors; however, they exhibit high interface leakage currents, causing low breakdown strength. Here, a ternary-blend strategy was used to synthesize polyvinyl chloride (PVC)/titanium carbide transition-metal carbide two-dimensional nanolayered material (Ti 2 C MXene)/diamond composites using solution casting. The PVC matrix exhibited low polarity and high insulation, while the Ti 2 C MXene and diamond fillers exhibited high conductivities and ultrahigh insulation properties, respectively. Overall, the PVC/Ti 2 C/diamond ternary composites exhibited better electrical properties than the PVC/Ti 2 C binary composites. In the ternary composites, PVC/Ti 2 C interface polarization caused high dielectric constants, while low leakage currents induced by diamond caused low dielectric losses and high breakdown strength. The optimum-composition (12 wt.% Ti 2 C and 4 wt.% diamond) ternary composite exhibited a high dielectric constant (~153 at 100 Hz), low dielectric loss (~0.14 at 100 Hz), low conductivity (~1.4 × 10 −6 S m −1 at 100 Hz), and high breakdown strength (~312 MV m −1 under a direct current field). This study indicates a synergistic effect between Ti 2 C MXene and diamond in the composite dielectrics, and could guide the fabrication of dielectric films for capacitors. Graphical Abstract
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2025
·
IF 6.3
Guohua Fan,Jinke Song,Yanan Tang,Xiaoting Song,Yao Liu
Dielectric modulation is arresting in electrical and electronic fields, and high- k is particularly important in applications like energy conversion and pulse power supply. Herein, an innovative strategy that different from conventional practices was adopted to boost the dielectric constant of PVDF-based dielectrics via involving an epsilon-negative layer in the laminates. The epsilon-negative layer was obtained based on the plasmonic state in percolating graphene networks. After stacking with the epsilon-positive layer containing core-shell BaTiO 3 @SiO 2 fillers, dielectric constant of the laminated composites was improved, and it increased constantly with the increasing thickness ratio of the epsilon-negative layer. It's ascertained the boost in dielectric constant was related to the multiple interfacial polarizations inside the layered composites, and the dielectric loss was suppressed by the low loss epsilon-positive layer. Therefore, synergism of epsilon-negative and positive layers in the enhancement of dielectric performance was elucidated, which developed a new avenue to obtain high- k dielectrics by the means of laminated composites.
研究领域:
材料科学
·
电气工程
✓ 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）