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1.
Rui Da Shi Lu Liu Xiao Li Zhu Xiang Ming Chen 《Journal of the American Ceramic Society》2022,105(2):1159-1172
In the present work, the physical properties modification by ordered domain engineering has been systematically investigated in Ba(Co1/3Nb2/3)O3 ceramics. The 1:2 ordered structure with an ordering degree up to 0.92 with uniform ordered domain size distribution is achieved in Ba(Co1/3Nb2/3)O3 ceramics after post-densification annealing, where the significantly enhanced electric resistivity, thermal conductivity, and dielectric strength, and subsequently the superior energy storage characteristics are achieved. The dielectric strength increases from 618 kV cm–1 to 972 kV cm–1 in the present ceramics by such means of ordered domain engineering, while the energy storage density increases from 0.65 J cm–3 to 1.42 J cm–3. There are three primary parameters in ordered domain engineering: ordering degree, ordered domain size and its distribution, and ordered domain boundary type. The final physical properties are determined by these three parameters. 相似文献
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本文讨论了复合钙钛矿型Ｂａ（Ｍｇ１／３Ｔａ２／３）Ｏ３中Ｂ位离子的有序程序同材料的介电损耗之间的关系。用Ｘ射线谱和Ｒａｍａｎ光谱研究了陶瓷烧结温度对Ｂａ（Ｍｇ１／３Ｔａ２／３）Ｏ３中Ｂ位离子的有序程度的影响，当适当提高烧结温度可增大有序程度。 相似文献
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Wenhui Ye Bo Yan Jinxu Ma Qiang He Linan An Kepi Chen 《Journal of the American Ceramic Society》2023,106(11):6858-6867
Recently, high-entropy perovskite oxides (HEPOs) have received increasing interest for energy storage applications owing to their unique structure, huge composition space, and promising properties. However, designing HEPOs with improved energy storage performance remains a challenge. In this study, various HEPOs were designed by partially replacing Zr4+ for Ti4+ in (Bi0.4Ba0.2K0.2Na0.2)TiO3 medium-entropy ferroelectric ceramics. The resulting ceramics exhibited a pseudo-cubic structure. With increasing Zr4+ content, the ceramics gradually transformed into relaxor ferroelectrics. The energy storage performance of the ceramics depended on the Zr4+ content. The sample with 20 mol% Zr4+ showed the best energy storage performance with a maximum reversible energy density of 2.47 J/cm3 and an energy storage efficiency of 82.3% at a low applied electric field (224 kV/cm). This study obtained a promising material for the new generation dielectric energy storage capacitors and provided a novel method for enhancing energy storage performance. 相似文献
6.
Rui Ze Guo;Xing Yu Chen;Yi Han Ding;Xi Wang;Xiao Li Zhu;Xiang Ming Chen; 《Journal of the American Ceramic Society》2024,107(9):6275-6284
Ba[(Ca0.2Mg0.2Zn0.2Co0.2Ni0.2)1/3Nb2/3]O3 and Ba[(Mg0.25Zn0.25Co0.25Ni0.25)1/3Nb2/3]O3 perovskite single-phase ceramics were synthesized by a solid-state reaction method, and they were annealed at different temperatures in order to investigate the effect of B′-site configurational entropy on phase stability, ordered domain structure and microwave dielectric characteristics. By comparing the B′-site high-entropy composition with B′-site medium-entropy and low-entropy compositions, the entropy-dominated phase-stabilization effect and sluggish diffusion effect were observed in Ba[(Ca0.2Mg0.2Zn0.2Co0.2Ni0.2)1/3Nb2/3]O3. These effects enhanced the temperature stability of the B-site 1:2 ordered structure. Ba[(Ca0.2Mg0.2Zn0.2Co0.2Ni0.2)1/3Nb2/3]O3 even reached a higher Qf value after annealing above the order-disorder transition temperature (To-d). This research extends the entropy regulation to ordered complex perovskite and provides a promising way to modify the performances of complex perovskite dielectric ceramics. 相似文献
7.
(1-y)Ca1-xLa2x/3TiO3-yCa(Mg1/3Nb2/3)O3复合微波介质陶瓷的研究 总被引：3，自引：0，他引：3
采用固相合成法制备了 ( 1-y)Ca1 -xLa2x/ 3 TiO3 -yCa(Mg1 / 3 Nb2 / 3 )O3 系列微波介质陶瓷材料 ,研究了复合系统的微波介电性能、烧结性能和微观结构。研究结果表明 :在y =0 .4～ 0 .6范围内 ,体系形成了单一的钙钛矿结构 ;当复合体系组成 0 .5Ca0 .6La0 .2 67TiO3 -0 .5Ca(Mg1 / 3 Nb2 / 3 )O3 时 ,在 14 0 0℃下烧结保温 4小时所得到材料的微波介电性能最佳 ;εf=5 5 ,Q×f =45 0 0 0GHz( 7.6GHz下 ) ,τf=0 .0 4ppm/℃。 相似文献
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《Ceramics International》2021,47(23):33162-33171
Relaxor ferroelectrics are promising candidates for energy storage equipment due to their excellent energy-storage properties. Lead-free (1-x)Bi0.38Na0.38Sr0.24TiO3-xBaSnO3 (abbreviated as BNST-100xBS) relaxor ceramics were synthesized by a traditional solid-phase sintering method. The influences of the addition of BaSnO3 dopants for the energy storage and dielectric temperature-stable properties of BNST-100xBS ceramics were systemically investigated. All samples exhibited a typical pseudo-cubic symmetry structure and obtained the dense microstructure. The ergodic relaxor behavior of all ceramics was observed and revealed a trend of increase as a function of composition. All samples showed a single grain conduction mechanism and the activation energy decreased with the addition of composition. It is related to the generation of oxygen vacancies induced by the defect dipoles. BNST-2.5BS ceramic exhibited an outstanding recoverable energy density of ~1.42 J/cm3 with the corresponding efficiency of ~79.7% at 115 kV/cm field. In addition, excellent temperature-stable permittivity (43–255 °C) was obtained for BNST-7.5BS ceramic. Hence, BNST-2.5BS ceramic revealed excellent energy density properties and BNST-7.5BS exhibited outstanding temperature-stable dielectric permittivity, which was beneficial to use in energy storage equipment and other device applications. 相似文献
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Shiyu Zhou Yongping Pu Xinyi Zhao Tao Ouyang Jiamin Ji Qianwen Zhang Canpeng Zhang Shikuan Sun Rong Sun Junjie Li Dawei Wang 《Journal of the American Ceramic Society》2022,105(7):4796-4804
In this study, a high-entropy perovskite oxide Sr(Zr0.2Sn0.2Hf0.2Ti0.2Nb0.2)O3 (SZSHTN) was first introduced to Na0.5Bi0.5TiO3 (NBT) lead-free ferroelectric ceramics to boost both the high-temperature dielectric stability and energy storage performance. Excellent comprehensive performance was simultaneously obtained in the 0.8NBT–0.2SZSHTN ceramic with high ε′ value (> 2000), wide ε′-temperature stable range (TCC < 5%, 52.4–362°C), low tanδ value in a wide range (<0.01, 90–341°C) and high energy storage performance (Wrec = 3.52 J/cm3, Wrec and η varies ±6.08% and ±7.4% from 20 to 150°C), which endows it the promising potential to be used in high-temperature environments. 相似文献
10.
Dielectric capacitors play a key role in high power electronics, electric vehicles, and medical devices. Due to the biodegradability, high thermal stability, and ease of processing, poly(lactic acid)-based (PLA) films are widely used in applications of tissue engineering, actuators, and sensors. In this investigation, PLA films are prepared using a solution casting method for high energy density capacitor applications. It is found that the stretched poly(d -lactic acid) (PDLA) film exhibits an energy density and charge discharge efficiency of 18.5 J cm−3 and 95%, respectively, at room temperature. Furthermore, after a heating time of 30 min at 100 °C, it is found that the energy density and chargedischarge efficiency of the stretched PDLA films are maintained at 11.2 J cm−3 and 76%, respectively. In comparison, the energy density and efficiency of the stretched PDLA film are 1.03-fold and 53% higher, respectively, than those of the stretched poly(vinylidene fluoride-hexafluoropropylene) film at 100 °C with the same heat treatment. Compared with a high temperature polyimide material, the energy density of the stretched PDLA film is 1.98-fold higher at 100 °C. The PLA-based material shows great promise for application in high energy density capacitors operating at a high temperature (100 °C). 相似文献
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Hao Li;Fei Liu;Kuan-Chang Chang;Xinnan Lin;Shaojun Liu; 《Journal of the American Ceramic Society》2024,107(9):6152-6163
The B-site cation ordering-disordering transition process of complex perovskite Ba(B′1/3B″2/3)O3-based microwave ceramics can be directly promoted by accelerating the mass transport process rather than depending on long-time annealing treatment. Clear evidences suggest that CuO doping is helpful in enhancing the densification process of Ba(Co0.7Zn0.3)1/3Nb2/3O3 (BCZN) ceramics and promoting the growth and coarsening of the ordering domain, facilitated by the formation of quasi-liquid CuO-xCu2O layers. The improvement of the 1:2 ordering degree is attributed to the accelerated mass transport process enabled by quasi-liquid CuO-xCu2O layers rather than long-time annealing treatment. Consequently, the Q×f values experience a significant increase from 21,200 to 69,300 GHz, owing to enhancements in the relative density and 1:2 ordering degree. CuO-doped BCZN ceramics achieve high 1:2 ordering degree and Q×f values at relatively low temperatures and for short periods of time, and more importantly, it circumvents conventional lengthy annealing processes (>30 h) effectively to promote its ordering transition. These findings underscore the potential of accelerating mass transport process to promote ordering-disordering phase transitions and improving dielectric properties of complex perovskite Ba(B′1/3B″2/3)O3-based microwave ceramics. 相似文献
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复合钙钛矿型驰豫铁电体是一类具有重要应用价值的铁电材料，有关其介电特性的研究不仅具有重要的理论意义，而且具有十分重要的实用价值。本文综述了铅基复合钙钛矿型驰豫铁电体介电理论研究进展。 相似文献
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采用固相合成法制备了(1-y)Ca1-xLa2x/3TiO3-yCa(Mg1/3Nb2/3)O3系列微波介质陶瓷材料.研究了复合系统的微波介电性能和微观结构.研究结果表明在y=0.4～0.6范围内,体系形成了单一的钙钛矿结构.当复合体系组成为0.5Ca0.6La0.267TiO3-0.5Ca(Mg1/3·Nb2/3)O3时,在1 400℃下烧结保温4 h所制备的材料表现出良好的微波介电性能εr=55,Q×f=45 000 GHz(7.6 GHz下),τf=0.04×10-6/℃. 相似文献
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《Ceramics International》2022,48(16):23044-23050
Nd[(Mg1-xZnx)1/2Ti1/2]O3 perovskite ceramics (x = 0, 0.2, 0.4, 0.6, 0.8) are prepared by the solid-state reaction method. The effects of Zn2+ substitution on the structure, microstructure, especially the B-site 1:1 cation ordering and microwave dielectric properties have been investigated. Sintered Nd[(Mg1-xZnx)1/2Ti1/2]O3 ceramics all adopt dense microstructure, along with increased dimensional uniformity as Zn2+ substitution. All the ceramics are confirmed to have B-site 1:1 ordered monoclinic perovskite structure with P21/n space group. Atomic mass difference of B-site elements might be an important factor affecting the B-site 1:1 cation ordering. HRSTEM observation suggest that the doped Zn2+ cations have roughly entered the Mg2+ sites to promote 1:1 cation ordering. The degree of the 1:1 cation ordering can be negatively reflected by the full width at half maximum (FWHM) of F2g(B) mode at 372 cm?1 in Raman spectra. With Zn2+ doping, the degree of the 1:1 cation ordering first increases then decreases, and reaches its maximum at x = 0.6. Meanwhile the best combination of microwave dielectric properties is obtained, as εr = 31.4, Q × f = 74,000 GHz, τf = ?44 ppm/°C. It is found that the long-range ordering not only decreases the dielectric loss but also affects the dielectric constant, providing a theoretical foundation to understand further the correlation between ionic configuration and microwave dielectric properties. 相似文献
15.
Rui Ze Guo Rui Da Shi Xiao Li Zhu Xiang Ming Chen 《Journal of the American Ceramic Society》2023,106(7):4275-4283
The ordered domain engineering was investigated for Ba[(Zn0.8Mg0.2)1/3Nb2/3]O3 microwave dielectric ceramics to synergistically modify the physical properties especially the temperature coefficient of resonant frequency τf and quality factor Q value together with the thermal conductivity. The ordered domain structure could be tailored and controlled by the post-densification annealing, and the fine ordered domain structures with high ordering degree and low-energy domain boundary were obtained in the present ceramics annealed around 1400°C for 24 h, where the Qf value was improved from 51 000 to 118 000 GHz, τf was suppressed from 30 to 25.5 ppm/°C. Moreover, the thermal conductivity at room temperature was increased from 3.79 to 4.30 W m−1 K−1, and the Young's modulus was improved from 98 to 214 GPa. The present work provided a promising approach for synergistic modification of physical properties in Ba-based complex perovskite microwave dielectric ceramics. 相似文献
16.
Ziming Cai Xiaohui Wang Wei Hong Bingcheng Luo Qiancheng Zhao Longtu Li 《Journal of the American Ceramic Society》2018,101(12):5487-5496
A series of ferroelectric ceramic models with grain and grain‐boundary structures of different sizes are established via Voronoi tessellations. A phase‐field model is introduced to study the dielectric breakdown strength of these ferroelectric ceramics. Afterward, the relation between the electric displacement and electric field and the hysteresis loop are calculated using a finite element method based on a classical and modified hyperbolic tangent model. The results indicate that as the grain size decreases, the dielectric strength is enhanced, but the dielectric permittivity is reduced. The discharge energy density and energy storage efficiency of these ferroelectric ceramics extracted from the as‐calculated hysteresis both increase along with a decrease in their grain size at their breakdown points. However, under the same applied electric field, the ferroelectric ceramic with a smaller grain size possesses a lower discharge energy density but a higher energy storage efficiency. The results suggest that ferroelectric ceramics with smaller grain sizes possess advantages for applications in energy storage devices. 相似文献
17.
Yiting Long;Can Qu;Yuting Kang;Xu Huang;Pengfei Zan;Junshu Chen;Xiaoyan Sun;Qinlin Yu;Yatang Dai;Wei Wang;Linyu Pu;Huan Zhang; 《Polymer Composites》2024,45(5):4605-4617
In order to prepare polymer dielectric materials with high energy storage density, a series of polyimide (PI) based Janus composite films were prepared by metal–organic frameworks (MOFs) material (UiO-66) with high dielectric constant (ɛr) and boron nitride nanosheets (BNNSs) with high breakdown strength (Eb). As reported, the UiO-66 can significantly improve the ɛr of the composites. The ɛr of 20 wt% UiO-66/PI film is 10.51 at 103 Hz, which is 3.1 times that of pure PI film (3.39 at 103 Hz). However, the Eb of 20 wt% UiO-66/PI is only 58 MV m−1, which is only 16.51% of pure PI (352 MV m−1). The sharp decline in Eb reduces the energy storage capacity of the composites. To solve this problem, first, BNNSs with an average diameter of 2 μm and a thickness of 1.36 nm (about 4–5 layer) were obtained by hydrothermal reflux stripping. BNNSs/PI//UiO-66/PI Janus composite films with double-layer structure were prepared by directly casting BNNSs/PI on the surface of UiO-66/PI. For 0.3 wt% BNNSs/PI//10 wt% UiO-66/PI, the calculated energy storage density (Ue) is 5.75 J cm−3 at 140 MV m−1, which is 3.57 times that of pure PI film (1.61 J cm−3 at 140 MV m−1). Meanwhile, the charge discharge efficiency is 82.55% (at 140 MV m−1). 相似文献
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《Ceramics International》2016,42(16):18087-18093
Ba3CaNb2O9 is a 1:2 ordered perovskite which presents a trigonal cell within the D3d3 space group. Dense ceramics of Ba3CaNb2O9 were prepared by the solid-state reaction route, and their microwave dielectric features were evaluated as a function of the sintering time. From Raman spectroscopy, by using group-theory calculations, we were able to recognize the coexistence of the 1:1 and 1:2 ordering types in all samples, in which increasing the sintering time tends to reduce the 1:1 domain, leading to an enhancement of the unloaded quality factor. We concluded that this domain acts as a lattice vibration damping, consequently raising the dielectric loss at microwave frequencies. The best microwave dielectric parameters were determined in ceramics sintered at 1500 °C for 32h: ε′ ~ 43; Qu×fr = 15,752 GHz; τf ~ 278 ppm °C−1. 相似文献
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Xianwu Cao;Nahong Zhang;Lu Zhao;Chonghao Lu;Chunhui Bi;Guangjian He;Wei Wu; 《Polymer Composites》2024,45(5):4447-4458
The inherent low dielectric constant of polyimide (PI) dielectrics restricts their applications to become a component of high energy density film capacitors. In this work, double core–shell structured barium titanate@magnesium oxide@polydopamine (BaTiO3@MgO@PDA) nanoparticles were synthesized successfully and utilized as high dielectric constant functional fillers for PIs, in which the insulating MgO layer meliorated dielectric constant difference between BaTiO3 and PI matrix, and the organic PDA layer improved the compatibility between the inorganic fillers and PI matrices. Then, a series of sandwich-structured PI-based hybrid films was prepared through a layer-by-layer solution casting method. The middle layer of pure PI with excellent insulating properties effectively suppressed charge injection. With the combination of sandwich structure and the BaTiO3@MgO@PDA nanoparticles, the PI hybrid film containing 15 wt% fillers in the outer layers achieved the maximum breakdown strength of 425.68 kV/mm and the maximum energy density of 5.132 J/cm3, which was 68.3% and 413% higher than those of pure PI film, respectively, meanwhile maintained a low dielectric loss value of 0.0083 at 1 kHz. The introduction of BaTiO3@MgO@PDA enhanced the interfacial polarization due to the high barrier energy between adjacent layers preventing the transfer of electrons and weakening the leakage current in the sandwich-structured composite film. This work demonstrates that an appropriate combination of high dielectric hybrid fillers and multilayer structure can effectively increase the energy storage density of PI substrate for high-temperature energy storage applications. 相似文献