ACS Applied Polymer Materials
·
2019
·
IF 0
Chao Qian,Tianwen Zhu,Weiwen Zheng,Runxin Bei,Siwei Liu,Dingshan Yu,Zhenguo Chi,Yi Zhang,Jiarui Xu
Surface hydroxylation was implemented on CaCu3Ti4O12 (CCTO) particles to improve their interface compatibility and dispersibility in polyimide matrix. The surface hydroxylated CCTO fillers (CCTO–OH) were obtained by treating the CCTO particles in the mixed solution of H2SO4 and H2O2. The experimental results showed that the CCTO–OH/polyimide (PI) composite films had higher dielectric permittivity and lower coefficient of thermal expansion (CTE) compared to those of the CCTO/PI composite films, which were mainly attributed to the good dispersion of CCTO–OH particles and the enhanced interfacial polarization between CCTO–OH particles and PI chains. Among these CCTO–OH/PI composite films, the composite film with 40 vol % CCTO–OH particle loading exhibited the highest dielectric permittivity (76.9, 102 Hz), and a low dielectric loss (0.2, 102 Hz) was maintained. The maximum discharge energy density of the CCTO–OH/PI composite film with 25 vol % CCTO–OH reached 1.31 J/cm3, which was almost twice that of pure PI (0.63 J/cm3). Further, the prepared CCTO–OH/PI composite films had excellent heat resistance and low CTE. The high-k property of the CCTO–OH/PI composites remained stable up to 300 °C, which is probably the most heat-resistant dielectric material reported in the literature and is absolutely critical for the manufacture of electronic devices facing extreme conditions.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2021
·Vol. 32
·期 17
·21923-21931
·
IF 2.478
Wu Ruifeng,Lin Yuanwei,Liu Yafei,Chang Aimin,Zhao Pengjun,Zhang Bo
In this study, x LaMnO 3 -(1 − x )CaCu 3 Ti 4 O 12 (0 ≤ x ≤ 0.7) composite ceramics have been prepared by the conventional solid-state method. XRD results show that the composite ceramics are mainly composed of LaMnO 3 and CaCu 3 Ti 4 O 12 phases. Electrical property analysis shows that the resistivity ρ 25 gradually decreases from 2.17 × 10 8 to 1.74 × 10 5 Ω·cm with increasing LaMnO 3 content. The relationship between ln ρ and 1000/ T is not linear and changes around 350 °C. In the temperature range of 0–350 °C, the activation energy E a 0–350 °C decreases gradually with the increase of the LaMnO 3 content. In the temperature range of 350–500 °C, the activation energy E a 350–500 °C increases first and then decreases, which is related to the variation of oxygen vacancy. The compounding of LaMnO 3 gives rise to the decrease in B value, thus, providing the potential for the applications of wide temperature range thermistors. After annealing, the coefficient of aging (Δ R / R ) of the composites decreases from 23.73 to 3.01%.
研究领域:
材料科学
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电气工程
✓ 已验证
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 23
·5824
·
IF 3.1
Guoyu Zhang,Lu Li,Yanxin Nan,Peng Li,Tao Deng,Zhipeng Lei,Yuanyuan Li,Jianhua Zhang
In this work, the effects of different sintering temperatures and TiO2concentrations on the dielectric properties of ZrO2and Nb2O5pre-doped CaCu3Ti4O12(CCTO) ceramics were investigated. These doped ceramics were sintered at temperatures of 1020, 1030, and 1040 °C, exhibiting the lowest dielectric loss of 0.01, which consistently remained below 0.03 across a wide frequency range from 10 to 105Hz. Simultaneously, they maintained a high dielectric constant of more than 3000 and remarkably met the requirements for an X8P capacitor (Δε′ ≤ ±10% at temperature range from −55 to 150 °C). It was clarified that TiO2doping increased grain boundary resistance, leading to the reduced dielectric loss, and elevated the grain boundary activation energy, thereby enhancing the temperature stability. The TiO2-doped CCTO-based ceramics also demonstrated reduced sensitivity to variations in sintering temperature, highlighting their excellent manufacturability. This characteristic holds great promise for the fabrication of CCTO-based ceramics, which usually exhibit poor repetitiveness.
研究领域:
材料科学
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电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2023
·Vol. 11
·期 35
·12037-12047
·
IF 6.4
Ruifeng Wu,Haibing Li,Yafei Liu,Aimin Chang,Bo Zhang
It is found that the linearization of the resistance–temperature curve for CaCu3Ti4O12 can be achieved by changing the energy band structure induced by Fe3+, but at the cost of decreasing temperature sensitivity. Here, a novel strategy is proposed to improve the thermal and dielectric properties of CaCu3Ti4O12 ceramics by (La,Fe)-co-doping. This can both linearize the resistance–temperature relationship by adjusting the energy band structure of the grains due to the Fe3+ doping and improve the temperature sensitivity by increasing the grain boundary potential barrier resulting from La3+ doping. The dielectric constant increases upon decreasing the grain boundary potential barrier and increasing the carrier concentration. Therefore, the dielectric constant and temperature sensitivity can be regulated by adjusting the characteristics of grains and grain boundary. This work bridges the relationship between thermal sensitivity and dielectric properties, and opens up a door for the development of a multifunctional coupler CaCu3Ti4O12 device.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2025
·
IF 5.7
Wei Wan,Jie Zhou,Yan Li,Jiamin Xiao,Junrong Luo,Yuqian Yang,Lei Yu,Yuejun Ouyang
Flexible dielectrics with exceptional dielectric properties are highly desirable for various electronic applications. In this study, we successfully fabricated CaCu 3 Ti 4 O 12 (CCTO)/Ti 3 C 2 T x MXene/millable polyurethane (MPU) ternary composite films via a combination of mixing and hot compression techniques. The incorporation of 2D Ti 3 C 2 T x MXene nanosheets at a mass fraction of 4 % significantly enhanced the dielectric properties of the composite films. Specifically, the dielectric constant at 100 Hz increased to 41.1, representing a 14.48 % improvement over the initial CCTO/MPU composite. Meanwhile, the dielectric loss remained low at 0.050, with only a marginal increase of 2.04 %. Additionally, the breakdown strength of the composite films was notably boosted to 19.15 kV/mm, demonstrating a 15.3 % enhancement. These findings highlight the substantial improvement in the dielectric performance of the CCTO/Ti 3 C 2 T x /MPU ternary composite films, showcasing their potential for high-performance electronic applications.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Qi Bu,Shuang Yin,Wei Wan,Sisi Zeng,Shiyao Zhou,Lei Yu,Yuejun Ouyang
Flexible CaCu 3 Ti 4 O 12 (CCTO)/polyurethane dielectric composite films were fabricated, and the effects of the silane coupling agent, 3-Aminopropyltriethoxysilane (KH550), on the dielectric properties of the composite films were investigated. It was found that using KH550 significantly improved interfacial compatibility between the CCTO filler and the polyurethane matrix, leading to the reduction of dielectric loss and conductivity, and an increase in the dielectric breakdown strength . At 100 Hz, the composite film with a 3 wt% KH550 dosage exhibited a dielectric constant of 53.1 and a dielectric loss of only 0.068 (a 73.8 % reduction compared to the composite film with untreated CCTO particles). The composite films with KH550-modified CCTO particles exhibited a maximum breakdown strength of 18.5 kV/mm, showing a 58.1 % increase compared to the composite film with untreated CCTO particles. Moreover, introducing KH550 was beneficial in reducing the variation of dielectric properties with temperature, thereby enhancing the reliability of polyurethane based dielectric composite materials in practical applications.
研究领域:
材料科学
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电气工程
✓ 已验证
产品关联
DOI
高影响因子
ECS Journal of Solid State Science and Technology
·
2020
·Vol. 9
·期 5
·053003
·
IF 2.142
Hanying Wang,Chunyuan Deng,Kai Sun,Yunpeng Qu,Runhua Fan
In this paper, FeCrNi/CaCu3Ti4O12 metacomposites with different FeCrNi content were fabricated by low-temperature presureless sintering process. With increasing FeCrNi content above percolation threshold, the conduction mechanism changed from hopping conduction to metal-like conduction. Meanwhile, epsilon-negative property was obtained at 70 wt%–90 wt% content of FeCrNi, ascribing to the low frequency plasmonic state from three-dimensional conductive FeCrNi networks. The correlation between epsilon-negative property and inductive character was clarified by reactance spectrum. This work benefited the exploration of metal/ceramic metacomposites which could facilitate their promising applications in invisibility, high-k capacitors, novel antennae and sensors.
研究领域:
材料科学
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电磁学
·
纳米技术
✓ 已验证
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 50
·31654-31662
·
IF 3.108
Jun Wang,Xilin Wang,Youwei Yao,Juyi Guo,Xiaogang Ouyang,Zhidong Jia
The application of polymer composites with electric field dependent nonlinear conductive and dielectric characteristics for high voltage equipment is an effective method to control electric field stress and disperse space charges. In this study, core-satellite CaCu3Ti4O12@ZnO fillers were synthesized and doped into silicone rubber composites, and compared to a mixture of CaCu3Ti4O12 and ZnO with the same filler concentration. The composites exhibited both nonlinear conductive and nonlinear dielectric properties with nanoparticle fillers for the first time. Both the nonlinear conductive coefficient and dielectric coefficient increased with filler concentration. The classical current-path model was utilized to explain the nonlinear conductive properties, while the interface-barrier-layer-capacitor model and double-depletion-layer model were introduced to explain the nonlinear dielectric properties, which would broaden the thinking for the fabrication of nonlinear 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
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·
IF 2.7
Man Liu,Chuandong Shi,Hongmei Qin,Chuanxi Xiong,Quanling Yang
The demand for dielectric capacitor materials has significantly increased, owing to the need for highly efficient operation at elevated temperatures amidst the rapid advancements in modern electronics. In this contest, fluorinated polyimide (FPI)/CaCu 3 Ti 4 O 12 (CCTO) composite films have been successfully fabricated through a straightforward blending approach. The modified CCTO (mCCTO) is prepared by first hydroxylation CCTO and subsequently by grafting KH550 onto its surface, a strategy aimed at enhancing the interfacial compatibility with FPI. The synergistic effect of the high dielectric constant and good dispersibility of CCTO inorganic fillers underscores the significant role of filler dispersibility in enhancing the high-temperature capacitive performance of polymer composite materials. The dielectric constant of FPI-mCCTO composite films containing 9 wt.% mCCTO reached 8.5 at 150°C, more than double that of pure FPI (3.0). Furthermore, the FPI-0.09-mCCTO composite films exhibited the highest discharge energy density of 4.92 J·cm −3 at 355 MV·m −1 . This facile approach provided a viable strategy for fabricating high-temperature dielectric materials for electrical energy storage.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 25
·1-13
·
IF 2.8
Yang Xiao-Yu,Yan Meng-Han,Zhang Ying,Zhang Zhi-Fei,Chen Xue-Shuai,Joshi Mahesh Kumar,Li Zi-Liang,Li Peng,Han Wei-Fang,Fu Peng
In this study, a series of perovskite-phase x LaCoO 3 -(1 − x )CaCu 3 Ti 4 O 12 [ x LC-(1 − x )CCTO, with x = 0.02, 0.04, 0.08, 0.15] negative temperature coefficient (NTC) ceramics were fabricated by a solid-state reaction method. XRD analysis indicated that the ceramics consisted of a body-centered cubic perovskite phase. The grain size of the prepared samples was greatly decreased by introducing LC. The decrease in resistivity of all samples as a function of temperature indicated the presence of NTC effect in all the fabricated x LC-(1 − x )CCTO ceramics. The electrical resistivity ρ 30 decreased within a relatively narrow range of 1.58 × 10 6 − 9.28 × 10 5 Ω cm with increasing LC content, whereas thermistor constant B 30/75 increased within a wide range of 2190–5232 K. Our outcomes confirmed that the combination of ρ 30 and B 30/75 could be adjusted to desired values by incorporating LC. In addition, in situ XPS and complex impedance analysis displayed a conduction mechanism based on electron hopping. Current research provided a feasible example to achieve the suitable coupling of high ρ and low B values for NTC thermistors.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2021
·Vol. 32
·期 7
·9324-9331
·
IF 2.478
Hao Wentao,Yu Bo,Xu Panpan,Sun Li,Cao Ensi,Zhang Yongjia
CaCu 3 Ti 4 O 12 (CCTO) is a very promising high dielectric permittivity ceramic, but the larger low-frequency dielectric loss limits its application. According to internal barrier layer capacitance effect, which is commonly accepted to explain the unusual dielectric properties of CCTO ceramic in the kHz frequency range, constructing insulating phase boundaries between CCTO grains is an effective method to reduce the low-frequency dielectric loss. Therefore, (In 0.5 Nb 0.5 ) 0.05 Ti 0.95 O 2 (INTO) ceramic powder, another high dielectric permittivity ceramic with much higher sintering temperature than CCTO, was added to CCTO ceramic powder to prepare CCTO/xINTO multiphase ceramics with the structure of INTO phase separating CCTO phase. The experimental results show that CCTO/xINTO multiphase ceramics with the designed structure have been obtained, and their low-frequency dielectric loss indeed decreases significantly compared with CCTO ceramic, which should be mainly attributed to the insulating INTO phase. The CCTO/INTO ceramic sintered at 1040 °C for 8 h in atmosphere exhibits good overall dielectric properties at room temperature, of which the low-frequency dielectric loss is less than 0.05 and the dielectric permittivity reaches 3000.
研究领域:
材料科学
·
电子材料
✓ 已验证
产品关联
DOI
高影响因子
Journal of Asian Ceramic Societies
·
2022
·
IF 2.546
Guang-Tan Miao,Zhen-Jie Wang,Peng Li,Ji-Gong Hao,Wei Li,Juan Du,Wei-Fang Han,Chun-Ming Wang,Guo-Rong Li,Peng Fu
The structure and electrical properties of CaCu3Ti4O12 (CCTO) ceramics doped with xHo2O3 synthesized by solid-phase reaction method were systematically studied. Insights from X-ray diffraction (XRD) measurements indicate the existence of a primary phase of CCTO in all samples. Ho2O3 dopant was found to inhibit grain growth and thus leading to a reduced grain size of ceramics. Moreover, the distribution of resistivity with temperature revealed the manifestation of a negative temperature coefficient (NTC) effect in the samples. More specifically, the resistivity (ρ20) values of obtained ceramics configurations decreased from 8.54 × 106 to 1.76 × 105 Ω cm with increasing Ho2O3 doping content. In addition, thermal constant (B20/75) of all samples was higher than 4000 K. Electrical properties analysis disclosed that electron hopping process is main conduction mechanism within CCTO-based ceramics. In addition, insights from complex impedance spectra revealed the existence of grain boundaries with resistance higher than grains resistance. This effect is strongly connected with the manifestation of electrical relaxation procedures within grain boundaries. Our outcomes verify that both the structural configuration and the electrical performance of the CCTO-based ceramics can be tuned directly and effectively by incorporating Ho2O3 dopant.
研究领域:
材料科学
·
电学
✓ 已验证
DOI
高影响因子
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