MATERIALS CHEMISTRY AND PHYSICS
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2021
·
IF 4.094
Yong Guo,Junlang Tan,Jingchang Zhao
CaCu 3 Ti 4 O 12 /CaTiO 3 (CCTO/CTO) composite ceramics were prepared through in-situ reaction and solid-state sintered at 1040°C for 10 h. The phase composition, microstructure, morphology, valence, and electrical properties of ceramics are systematically studied by X-ray diffraction(XRD), Field emission scanning electron microscopy(FESEM), Electron probe micro-analysis (EPMA), X-ray photoelectron spectroscopy(XPS), and LCR instruments. It can be found that the FESEM image shows that the addition of CTO inhibits the growth of CCTO grains, and there are nanocrystals inside the grains. The EPMA mapping demonstrated which nanocrystals are composed of CCTO and a small amount of CTO. Impedance spectroscopy observed two semi-circular arcs, which correspond to the effects of micron-level grains and nano-level nanocrystals, respectively. These two mechanisms significantly affect the colossal dielectric response of CCTO/CTO composite ceramics.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2020
·Vol. 31
·期 11
·8481-8488
·
IF 2.22
Zhang Jianhua,Li Zhuoxiao,Liu Yuqian,Zheng Jiecheng,Lu Wenmin,Guo Siqi,Lei Zhipeng,Lin Lingyan,Tian Muqin
In this work, effects of different halogen elements (F, Br, and I) on the microstructure, morphology, and dielectric properties of CaCu 3 Ti 4 O 12 (CCTO) ceramics prepared through sol–gel method were systematically studied. It was found that the dielectric loss of the CCTO ceramics doped with F reduced to 0.022 and the breakdown field strength increased to 9.4 kV/cm, simultaneously. Moreover, the Br-doped samples exhibited the lowest dielectric loss of 0.019 and the highest dielectric constant of about 82,047, while the breakdown field strength declined obviously compared to pure CCTO samples. However, in contrast to F or Br element, the I element did not significantly improve the dielectric properties of CCTO ceramics. In addition, the decreased dielectric loss for the doped CCTO ceramics could be owed to the increasing resistance of the grain boundaries, and the improved breakdown field strength could be attributed to the enhanced potential barrier height. All the results suggest that introducing anions, like halogen elements, is an efficient approach to improve the dielectric properties of CCTO ceramics.
研究领域:
材料科学
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无机非金属材料
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电子功能材料
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介电材料
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固态化学
✓ 已验证
DOI
高影响因子
Materials Today Communications
·
2025
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IF 4.5
Zefeng Guo,Jianhua Zhang,Yongke Yan,Guoyu Zhang,Dongdong Liu,Zhipeng Lei,Yuanyuan Li,Lu Li
Achieving both low dielectric loss (tan δ ) and high temperature stability of ceramic capacitors can greatly broaden their potential application. In this study, the effects of Mg and Al co-substitution on the microstructure and dielectric properties of CCTO-based ceramics were investigated in CaCu 3- x Mg x Ti 4- x Al x O 12 ( x = 0, 0.025, 0.050, and 0.075) ceramics prepared by a sol-gel method. XRD analysis shows that the primary crystalline phase of CCTO is formed in all samples, indicating that Mg 2 + and Al 3+ have entered the lattice. SEM results reveal the co-substitution of Mg and Al inhibits the grain growth, leading to an increase in grain boundary density. All co-substituted samples exhibited low tan δ and excellent temperature stability. Notably, CaCu 2.95 Mg 0.05 Ti 3.95 Al 0.05 O 12 ceramics exhibited an extremely low tan δ of 0.007 (at 10 3 Hz) and its dielectric constant maintained excellent stability over a broad temperature spectrum (−125 to 150 °C), meeting the commercial standards for X8P capacitors. The reduction of tan δ is mainly attributed to the inhibition of grain growth in Mg and Al co-substituted samples, which increases grain boundary density and subsequently suppresses the mobility of oxygen vacancies, leading to an increase in grain boundary resistance. Furthermore, the improvement in temperature stability is ascribed to the reduction in the content of oxygen vacancies and the suppression of electron transitions between Ti 4+ and Ti 3+ as well as Cu 2+ and Cu + in Mg and Al co-substituted samples, resulting in an increase in grain boundary activation energy. These novel findings are hoping to contribute to not only the fabrication of new CCTO-based ceramics with extremely low tanδ and excellent temperature stability but also the application of CCTO-based ceramics at a very broad temperature range in electronic devices, new energy vehicles, aerospace, and polar scientific research equipment.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2021
·Vol. 9
·期 46
·26010-26018
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IF 12.732
Junhao Jiang,Jinpeng Li,Jun Qian,Xiaoyun Liu,Peiyuan Zuo,You Yuan,Qixin Zhuang
Polymer nanocomposites with high energy density have become a research hotspot in the field of dielectric materials. However, the huge compatibility contrast between nanofillers and polymers always hinders the further improvement of dielectric properties. Meanwhile, next-generation dielectrics should possess excellent thermal stability to cope with the development of high-temperature applications. Herein, a novel polymer nanocomposite based on heat-resistant poly(p-phenylene benzobisoxazole) (PBO) and high-permittivity CaCu3Ti4O12 (CCTO) nanoparticles was prepared by the solution method. In this process, electroactive polymer poly(2-isopropenylbenzoxazole) (P(2-IBO)), which has a chemical structure similar to PBO and contains numerous permanent dipoles, is selected as the modifier to optimize the electric field behavior at the interface, and it is coated on the surface of CCTO nanoparticles via surface-initiated reversible addition–fragmentation chain transfer (RAFT) polymerization for achieving controllable dielectric properties. The results demonstrate that the dielectric properties can be adjusted by changing the thickness of the P(2-IBO) shell. The breakdown strength and energy density of the modified CCTO/PBO nanocomposites are much higher than those of the unmodified CCTO/PBO nanocomposites. Under an electric field of 200 kV mm−1, the maximum discharge energy density reaches 3 J cm−3, which is about 500% that of pure PBO (0.6 J cm−3). Moreover, the dielectric properties are nearly independent of the testing temperature (25 to 200 °C), indicating that this nanocomposite is an ideal candidate for high-temperature dielectric materials.
研究领域:
材料科学
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高分子化学
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电介质材料
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Chemistry
·
2025
·
IF 6.7
Mengyuan Zhang,Wenying Zhou,Xiaoyan Lei,Jiahuan Zhao,Ying Li,Jing Zuo,Xinyang Jia,Jian Wang
Polymer composites combining high dielectric permittivity ( ε ), low dielectric loss, and superior breakdown strength ( E b ) exhibit significant industrial application prospects. To achieve excellent overall dielectric properties in calcium copper titanate (CCTO)/poly (vinylidene fluoride, PVDF) composites, the alumina (Al 2 O 3 ) encapsulated CCTO particles were prepared via a sol-gel technology and subsequently added into PVDF to explore the interlayer’ impact on the morphology and dielectric performance. The results demonstrate that the Al 2 O 3 shell simultaneously improves interfacial compatibility between the two components and thereby reduces both dielectric loss and electrical conductivity in the CCTO@Al 2 O 3 /PVDF. Moreover, the CCTO@Al 2 O 3 /PVDF composites showcase superior E b relative to pure CCTO/PVDF, as the Al 2 O 3 interlayer homogenizes the electric field distribution by mitigating dielectric mismatch and introduces charge-trapping sites that restrict carrier mobility, thereby mitigating electric field distortion and inhibiting electrical tree growth. Precise regulation and control of the Al 2 O 3 thickness enables effective tuning of the overall dielectric properties in CCTO@Al 2 O 3 /PVDF composites. Theoretical analysis unlocks the fundamental polarization mechanisms and the modulated charge transport behavior in modified CCTO/PVDF composites. This study establishes a novel strategy for developing flexible polymer dielectrics combining concurrently high E b and ε , coupled with low loss, presenting promising application prospects in power electronics and high-voltage insulation systems.
研究领域:
材料科学
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聚合物复合材料
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介电材料
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电气工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Yu Zeng,Shipeng Rao,Chenhan Xiong,Guoping Du,Zhaoyang Fan,Nan Chen
Dielectric polymer composites with conducting fillers would have great potential for diverse applications if their severe leakage loss could be addressed. In this regard, ternary composites using both ceramic and conducting materials as fillers might be an enabler for high dielectric constant and low dielectric loss. Herein, ternary composites with both Ti 3 C 2 T x MXene conducting nanosheets and CaCu 3 Ti 4 O 12 (CCTO) dielectric particles embedded in silicone rubber were studied. It was found that a ternary composite with 1.2 wt% (0.40 vol%) Ti 3 C 2 T x MXene and 12 wt% (2.58 vol%) CCTO could provide an overall superior performance that include a high dielectric constant of 8.8, low dielectric loss of less than 0.0015, good thermal stability up to 450 °C, and excellent mechanical properties with tensile strength of 569 kPa, elastic module of 523 kPa and elongation at break of 333%. The outstanding performance is attributed to the improved uniform dispersion and good interfacial compatibility of mixed fillers in the polymer matrix , suggesting ternary composites might be a better option over their binary counterparts in preparing high performance dielectric composites.
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
JOURNAL OF ELECTRONIC MATERIALS
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2026
·
IF 2.8
Qin Xueying,Jiang Jia,Yin Shuang,Zhang Yeming,Wan Wei
The development of calcium copper titanate (CaCu 3 Ti 4 O 12 , CCTO) ceramics is often hindered by their high dielectric loss, which limits practical applications. In this work, CCTO powder with tailored micrometer-sized particles, synthesized via a Na 2 SO 4 molten-salt method, was used to fabricate nano-SiO 2 -doped ceramics through an environmentally friendly, water-based gelcasting process with glutinous rice flour as a nontoxic binder. This approach enabled stable slurry processing and effective microstructural control. The incorporation of 3.5 wt.% nano-SiO 2 yielded optimal dielectric performance, achieving a high dielectric constant of 8091 and a significantly reduced loss tangent of 0.08 at 1 kHz; this represents a 71.4% reduction in loss compared to the undoped sample. Microstructural and electrical analyses confirmed that the nano-SiO 2 predominantly segregated at the grain boundaries, forming a continuous amorphous insulating layer. This phase enhanced grain boundary resistivity, optimized the electrical heterogeneity, and substantially improved the frequency and temperature stability of the dielectric properties. This study demonstrates that nontoxic gelcasting combined with nano-SiO 2 doping is an effective and sustainable strategy for tailoring the dielectric properties of CCTO ceramics toward high-performance electronic applications by optimizing the internal barrier layer capacitor structure.
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2019
·
IF 3.355
Jianhua Zhang,Jiecheng Zheng,Yuqian Liu,Chengzhong Zhang,Wentao Hao,Zhipeng Lei,Muqin Tian
In this work, the microstructure and dielectric properties of CaCu 3 Ti 4 O 12 (CCTO) ceramics based on sol-gel method prepared via different cooling methods (furnace cooling, air quenching, and water quenching) were systematically studied. The results showed that the dielectric constant of quick quenching samples (air quenching and water quenching) did not drop a lot contrasting to that of the furnace cooling CCTO ceramics. Furthermore, it was also found that the dielectric loss of air quenching CCTO ceramics decreased to 0.030, which was about 40% of the furnace cooling CCTO ceramics (0.074), and the dielectric loss of water quenching samples was as low as 0.044. In addition, the breakdown electric field could also be improved by air quenching. These enhancements could be attributed to the improved properties of the grain boundaries. The results above indicate that a proper quenching method can promote the dielectric properties of CCTO ceramics efficiently.
研究领域:
材料科学
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陶瓷
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介电材料
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固态物理
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Fukun Niu,Xueqian Li,Zhuqun Shi,Chuanxi Xiong,Quanling Yang
With the continuous development and progress of science and technology, the widespread use of petroleum-based plastics has highlighted serious environmental issues. Scientists are committed to replacing some of the applications of petroleum-based plastics with sustainable natural polymer materials. Chitin, cellulose, and other natural polymers rich in polar groups are suitable for designing and preparing sustainable and low-polluting dielectric energy storage materials. In this study, we selected calcium copper titanate (CCTO) with ultra-high dielectric constant as a dielectric enhancement filler and explored the effects of different morphological structure fillers on the dielectric energy storage properties of composite films. CCTO nanoparticles and CCTO nanofibers were mixed with chitin solution and cast into chitin/CCTO composite films. The one-dimensional CCTO nanofibers showed a more significant improvement in the comprehensive performance of the composite films. When the addition amount was 3 wt%, the breakdown field strength of the composite film was 410 MV m −1 , the charge-discharge efficiency was 78.2 %, and the energy storage density reached 6.14 J cm −3 , showing an obvious improvement compared with the pure chitin film and chitin/CCTO nanoparticles composite films. It is possible that the high aspect ratio structure fillers can enhance the inhibition of electric branches and provide better compatibility with the matrix.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2026
·
IF 5.6
Dongxu Wang,Miao Pan,Wen-Jie Chen,Zhibin Cheng,Xiaoyang Pan
Novel CaCu 3- x Zn x Ti 3.95 Zr 0.05 O 12 (CCZTZO, x = 0.025 - 0.1) ceramics were synthesized via a sol-gel route to optimize the intrinsic dielectric limitations of CaCu 3 Ti 4 O 12 (CCTO). Systematic investigation of Zn 2+ and Zr 4+ co-doping effects and annealing temperature variations (900 - 1050 °C) on microstructure and dielectric characteristics revealed: XRD analysis confirmed phase-pure CCZTZO crystallization with complete elimination of secondary phases after organic binder removal via re-sintering at 1000 °C. SEM and XPS characterizations validated successful dopant incorporation, demonstrating a monotonic reduction in grain size with increasing Zn 2+ content. Impedance spectroscopy revealed enhanced electrical resistance and substantially reduced dielectric loss tangent (tanδ) while maintaining high dielectric constants (ε′). Optimal performance was achieved in CaCu 2.9 Zn 0.1 Ti 3.95 Zr 0.05 O 12 (CCZTZO-4), exhibiting an low tanδ of 0.002 with high ε′ ≈ 1.27 × 10 3 . Furthermore, excellent frequency stability was observed across 10 2 Hz - 10 5 Hz, with ε′ maintained at ∼10 3 and tanδ consistently between 0.002 - 0.054. Temperature-dependent measurements revealed outstanding thermal stability with a relative permittivity coefficient Δε′/ε′ 25°C ≤ ±10 % over − 60 °C to 120 °C. Analysis of electrical modulus and impedance spectra indicated modified activation energies for both bulk and grain boundary responses, demonstrating that Zn 2+ and Zr 4+ co-doping effectively enhances the interfacial polarization mechanism in CCTO-based ceramics.
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
·
IF 4.65
Yunpeng Qu,Yulin Wu,Jiada Wu,Kai Sun,Runhua Fan
Metacomposites with simultaneous epsilon-negative and mu-negative property have drawn tremendous attentions due to their promising applications in electromagnetic field. Herein, Ni/CaCu 3 Ti 4 O 12 (Ni/CCTO) metacomposites were prepared by low-temperature pressureless sintering method. It was observed that Ni chains were gradually interconnecting to each other with increasing Ni content, and a percolation behavior was observed. Epsilon-negative property was obtained above percolation threshold attributing to the synergistic effect of induced electric dipole and low-frequency plasma oscillation in Ni networks, which was explained by the superposition of Drude and Lorentz model. Mu-negative property was observed above ∼34 MHz and ∼120 MHz for 60 wt% and 70 wt% Ni/CCTO composites respectively, which may originate from the combined effects of diamagnetic response, domain wall motion and gyromagnetic spin rotation. Hence, simultaneous epsilon-negative and mu-negative property at radio-frequency region was realized in Ni/CCTO metacomposites. Besides, the composites presented hopping conduction behavior, and then changed into metal-like conduction behavior with increasing Ni content. The impedance response of Ni/CCTO composites clarified the correlation between epsilon-negative and inductive character. This work could broaden the scope of metacomposites and pave its way to potential applications of electromagnetic shielding, novel antenna, and high- k capacitors.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
Functional Materials Letters
·
2021
·
IF 2.17
Baogang Ding,Yunpeng Qu,Kai Sun,Runhua Fan
Epsilon-negative ( ? ′ < 0) and epsilon-near-zero (ENZ) property was demonstrated in titanium carbide/copper calcium titanate (TiC/CCTO) metacomposites. Benefiting from the moderate concentration of free electrons in TiC filler and its adjustable three-dimensional (3D) networks, weakly negative permittivity ( ∼ − 200 at 20 MHz) was achieved. Not only that, tailoring the negative permittivity of metacomposites from ∼ − 200 to ∼ − 2060, ∼ − 4200, ∼ − 14000 and ∼ − 70000 at 20 MHz was realized by simply increasing TiC content. Besides, Drude model was used to explain the radio-frequency (RF) negative permittivity and quantified the collective plasma oscillation in TiC networks.
研究领域:
材料科学
·
电磁学
✓ 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）