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Haijuan Li Jian Zhuang Alexei A. Bokov Nan Zhang Jie Zhang Jinyan Zhao Wei Ren Zuo-Guang Ye 《Journal of the European Ceramic Society》2021,41(1):310-318
Mutiferroic materials like bismuth ferrite BiFeO3 have attracted much interest in the last decade due to their promising potential for such applications as spintronics and magnetoelectric data storage devices. On the other hand, relaxor ferroelectrics have been intensively studied for their complex structures with quenched disorder and polar nanoregions which play an important role in their outstanding piezoelectric performance. Much less studied are the single-phase multiferroics that exhibit ferroelectric and/or magnetic relaxor behavior and the correlation between their structure and intricate magneto-electric interactions. In this work, we investigate the evolution of the structure and relaxor behavior in the solid solution between the complex perovskite multirelaxor Pb(Fe2/3W1/3)O3 [PFW] and canonical multiferroic BiFeO3 [BFO], (1-x)PFW-xBFO (with a solubility limit of x = 0.30). The temperature dependences of the dielectric permittivity and loss tangent measured in the frequency range from 100 Hz to 1 MHz indicate characteristic relaxor ferroelectric properties for compositions of x ≤ 0.15, with a frequency-dependent dielectric permittivity peak and its temperature, Tm, satisfying the Vogel-Fulcher law. Detailed studies of the evolution of the relaxor behavior with composition reveal that Tm decreases firstly with a small amount (x = 0.05) of BFO substitution and then increases with further increase of BFO concentration. The degree of relaxor character, as defined by ΔTm [Tm (1 MHz) - Tm (100 Hz)], increases monotonously with increasing BFO content, signifying an enhancement of relaxor behavior with BFO substitution, which is confirmed by the Lorenz-type quadratic variation of the static permittivity. A temperature - composition phase diagram is constructed in terms of the characteristic Burns temperature (TB) and freezing temperature (Tf), which delimits a paraelectric state (PE) above TB, a non-ergotic relaxor state (NR) below Tf, and an ergotic relaxor state (ER) in between. The observed enhancement of relaxor behavior is explained by an increase in the number and size distribution of polar nanoregions in the ER phase, resulting from increased compositional and charge disorders as a result of BFO substitution. The evolution of relaxor behavior and its microscopic mechanisms studied in this work are insightful for a better understanding the multirelaxor properties in multiferroics. Moreover, further substitution of BFO (x ≥ 0.2) flattens the permittivity curves and leads to a temperature-stable variation of high dielectric constant (≈ 103) in a wide temperature range, making the PFW-BFO solid solution attractive for such applications as high energy density capacitors. 相似文献
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Coexistence of Ferroelectric Phases and Phonon Dynamics in Relaxor Ferroelectric Na0.5Bi0.5TiO3 Based Single Crystals 下载免费PDF全文
Jiajun Zhu Jinzhong Zhang Kai Jiang Haiwu Zhang Zhigao Hu Haosu Luo Junhao Chu 《Journal of the American Ceramic Society》2016,99(7):2408-2414
A combination of polarized Raman technique, infrared reflectance spectra, and first‐principles density‐functional theoretical calculations were used to investigate structure transformation and lattice vibrations of Na0.5Bi0.5TiO3, Na0.5Bi0.5TiO3–5%BaTiO3, and Na0.5Bi0.5TiO3–8%K0.5Bi0.5TiO3 single crystals. It was found that Na0.5Bi0.5TiO3 is of a two‐phase mixture with rhombohedral and monoclinic structures at room temperature. Correspondingly, three Raman‐active phonon modes located at 395, 790, and 868 cm?1, which were previously assumed as A1 modes of rhombohedral phase have been reassigned as A′′, A′, and A′ modes of monoclinic phase in the present work. In particular, a strong low‐frequency A′′ mode at 49 cm?1 was found and its temperature dependence was revealed. Two deviations from linearity for the abrupt frequency variation in the A′′ mode and Ti–O bond have been detected at temperatures of ferroelectric to antiferroelectric phase transition TF–AF and dielectric maximum temperature Tmax. The appearance of Na–O vibrations at 150 cm?1 was found below Tmax, indicating the existence of nanosized Na+TiO3 clusters. The observed Raman and infrared active modes belonging to distinct irreducible representations are in good agreement with group‐theory predictions, which suggests 9A1+9E and 36A′′+24A′ modes for the rhombohedral and monoclinic phases of Na0.5Bi0.5TiO3, respectively. 相似文献
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Yueyun Zhang Hui Liu Shengdong Sun Shiqing Deng Jun Chen 《Journal of the American Ceramic Society》2021,104(1):604-612
Lead-based ferroelectric materials are extensively employed in industrial applications and everyday life due to their excellent ferroelectric and piezoelectric performance. Pb(Ni1/3Nb2/3)O3-PbTiO3 (PNN-PT) is a typical binary relaxor ferroelectric system, whose refined structure and piezoelectric properties have not been systematically investigated. In this study, evolution of electric field-based crystal structure and variation of ferroelectric, piezoelectric, as well as dielectric properties with composition and temperature of (1 − x)PNN-xPT (0.32 ≤ x ≤ 0.36) ceramics were studied in full detail. The optimal performance is obtained at 0.66PNN-0.34PT with maximum piezoelectric coefficient d33 of 560 pC/N and large dielectric constant of 28 684. In situ high-energy synchrotron diffraction was employed to determine structural origins of enhanced properties of 0.66PNN-0.34PT. Interestingly, crystal structure of poled 0.66PNN-0.34PT ceramic is determined to be single monoclinic phase. Furthermore, both its lattice parameters and volume variation present butterfly shape under electric field. It is demonstrated that macroscopic strain of 0.66PNN-0.34PT stems mainly from intrinsic structure. The present study provides evidence for the relationship between microstructure and macroscopic properties, which is beneficial to the design of new materials with piezoelectric properties. 相似文献
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Longwen Wu Xiaohui Wang Zhengbo Shen Longtu Li 《Journal of the American Ceramic Society》2017,100(1):265-275
The (1?x)BaTiO3–xBi(Zn2/3Nb1/3)O3 (x = 0.01–0.30) ceramics were synthesized by solid‐state reactions. The solubility limit was determined to be x = 0.20. A systematic structural transition from a tetragonal phase (x ≤ 0.034), to a mixture of tetragonal and rhombohedral phases (0.038 ≤ x ≤ 0.20), and finally to a pseudocubic phase (x ≥ 0.22) at room temperature was identified. Dielectric measurement revealed a ferroelectric (x ≤ 0.04) to relaxor (x ≥ 0.06) transition with permittivity peak broadening and flattening, which was further verified by Raman spectroscopy and differential scanning calorimetry (DSC). Activation energies obtained from the Vogel–Fulcher model displayed an increasing trend from ~0.03 eV for x ~ 0.05, to unusually high values (>0.20 eV) for the compositions with x ≥ 0.15. With the increase in Bi(Zn2/3Nb1/3)O3 content, the polarization hysteresis demonstrated a tendency from high nonlinearity to sublinearity coupled with the reduction in remnant polarization and coervice field. The deconvolution of the irreversible/reversible polarization contribution was enabled by first‐order reversal curve distributions, which indicates that the decreasing polarization nonlinearity with the increase in Bi(Zn2/3Nb1/3)O3 concentration could be related with the change from the ferroelectric domain and domain wall contributions to the weakly coupled relaxor behaviors. 相似文献
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Shi‐Yu Liu Yang Meng Shiyang Liu De‐Jun Li Yaping Li Yingdi Liu Yaogen Shen Sanwu Wang 《Journal of the American Ceramic Society》2017,100(3):1221-1230
With extensive first‐principles calculations, we investigate the phase stability, electronic structures, and superconductivity properties of the BaPb1?xBixO3 (BPBO) and Ba1?xKxBiO3 (BKBO) perovskites with the cubic (C), tetragonal (T), and orthorhombic (O) phases. Our calculations show that the tetragonal superconducting phases of both perovskites are metastable. However, the orthorhombic phase of the BPBO perovskite in the superconductivity region is only slightly more stable than the tetragonal phase. The small energy difference between the T and O phases and the discontinuous T‐to‐O phase transition account for the experimentally observed coexistence of the T and O phases. On the other hand, the BKBO perovskite involves a large energy difference between the T and O phases, which induces a low equilibrium temperature of the discontinuous T‐to‐O phase transition, in agreement with the experimental observation that the tetragonal BKBO is maintained down to low temperatures. Moreover, the electronic structures of both BPBO and BKBO superconductors show a flat band near the Fermi level, which is favorable for superconductivity. Furthermore, we find that the longer the total length of the flat band segment is, the higher the critical temperature of the BPBO or BKBO perovskite is. This key finding could be generalized straightforwardly to other unconventional superconductors and can be used to design and find optimal composition with maximum Tc for new unconventional superconductors. 相似文献
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Compositional modifications of ferroelectric BaTiO 3 were systematically investigated for Nb +5 substituents ( x ). Relaxor ferroelectric behavior was induced for x ≥4 at%. 相似文献
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Narit Triamnak Rattikorn Yimnirun Jan Pokorny David P. Cann 《Journal of the American Ceramic Society》2013,96(10):3176-3182
The single‐phase solid solutions of the (1 ? x)BaTiO3–(x)Bi(Zn1/2Ti1/2)O3 (BT–BZT) where x = 0.02–0.15 were prepared to investigate dielectric properties. Crystal structure of samples was obtained by using an X‐ray diffraction technique and Raman spectroscopy. For compositions with x ≤ 0.08, the solid solutions exhibited clear tetragonal symmetry and transitioned to pseudocubic symmetry as the content of BZT increased. The dielectric response exhibited a sharp phase transition within the BT‐rich region and the composition 0.92BT–0.08BZT was characterized by the onset of relaxor characteristics. As the concentration of BZT increased, the phase transition exhibited broader and more diffuse behavior. The polarization as a function of electric field (P–E) of these solid solutions also exhibited the same trend. The BT‐rich compositions showed a normal ferroelectric P–E response with a decrease in loop area as the BZT content increased. The composition at x = 0.08 exhibited a pinched hysteresis loop and with further increase in BZT content, the P–E response was characterized by slim loops. 相似文献
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The processing of order-disorder perovskites Ba(In1/2Nb1/2)O3 (BIN), Ba(Inl/2Ta1/2)O3 (BIT), and the lead analogue Pb(In1/2Nb1/2)O3 (PIN) was investigated with an emphasis on improving and expanding our knowledge of microwave dielectric materials. Both BIN and BIT were shown to be paraelectric perovskites. The processing and annealing of PIN were related to the perovskite and its transformation to pyrochlore. Dielectric and physical characteristics were examined by X-ray diffraction profiles (XRD), scanning electron microscopy (SEM), and dielectric behavior. Attempts to enhance B-site cation order in PIN by thermal annealing were unsuccessful due to a pyrochlore formation. 相似文献
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Zihao Li Yuchun Wang Yanxue Tang Xiangyong Zhao Tao Wang Zhihua Duan Feifei Wang Xiaobing Li Chung Ming Leung Bijun Fang 《Journal of the American Ceramic Society》2021,104(1):313-321
High-quality ternary relaxor ferroelectric (100)-oriented Mn-doped 0.36Pb(In1/2Nb1/2)O3-0.36Pb(Mg1/3Nb2/3)O3-0.28PbTiO3 (Mn-PIMNT) thin films were grown on SrRuO3-buffered SrTiO3 single-crystal substrate in a wide deposition temperature range of 550-620°C using the pulsed laser deposition method. The phase structure, ferroelectric, dielectric, piezoelectric properties, and nanoscale domain evolution were studied. Under the deposition temperature of 620°C, the ferroelectric hysteresis loops and current-voltage curves showed that the film owned significantly enhanced remnant ferroelectric polarization of 34.5 μC/cm2 and low leakage current density of 2.7 × 10−10 A/cm2. Moreover fingerprint-type nanosized domain patterns with polydomain structures and well-defined macroscopic piezoelectric properties with a high normalized strain constant of 40 pm/V was obtained. Under in situ DC electric field, the domain evolution was investigated and 180° domain reversal was observed through piezoelectric force microscope. These global electrical properties make the current Mn-PIMNT thin films very promising in piezoelectric MEMS applications. 相似文献
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Structural and Piezoelectric Properties of (1−x)Pb(Zr1−yTiy)O3–xPb(Zn0.4Ni0.6)1/3Nb2/3O3 Ceramics Near Triple Point 下载免费PDF全文
Joon Hur Jong‐Hyun Kim Tae‐Gon Lee In‐Tae Seo Dae‐Hyeon Kim Sahn Nahm Chong‐Yun Kang 《Journal of the American Ceramic Society》2015,98(9):2887-2893
The crystal structure and piezoelectric properties of (1?x)Pb(Zr1?yTiy)O3‐xPb(Zn0.4Ni0.6)1/3Nb2/3O3 [(1?x)PZ1?yTy‐xPZNN] ceramics were investigated. The 0.665PZ0.45T0.55‐0.335PZNN ceramic has the triple point composition, where the rhombohedral, pseudocubic, and tetragonal structures coexist. Maximum d33 and kp values of 770 pC/N and 0.69, respectively, were observed from this specimen; it also exhibited a large εT33/εo value of 3250. Although the maximum d33 value was obtained from the triple point composition specimen, its g33 and d33 × g33 values were relatively small because of its large εT33/εo value. However, the 0.665PZ0.46T0.54‐0.335PZNN ceramic, which has a rhombohedral structure, exhibited a large g33 value of 43 × 10?3 Vm/N and a d33 × g33 value of 27 000 × 10?15 m2/N. Therefore, this ceramic is a good candidate for multilayer actuators and piezoelectric energy harvesters. 相似文献
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《Journal of the European Ceramic Society》2023,43(1):177-182
Relaxor ferroelectric behaviour was observed in perovskite layered structure (PLS) (Ca0.5Sr0.5Ba0.5Pb0.5)Nb2O7 (CSBPN) ceramics engineered using the high entropy approach. The CSBPN ceramics were sintered at 1350 °C and are single-phase with an orthorhombic structure (Cmcm space group) at room temperature. Their relaxor ferroelectric behaviour is characterized by a broad and frequency-dependent permittivity maximum and a current peak around zero electric field in the hysteresis loop. The presence of polar nanoregions is supported by piezoresponse force microscopy images. The value of the relative permittivity ?′ = 130 at 1 kHz and room temperature is much larger than that for conventional PLS ceramics Sr2Nb2O7 (?′ = 42) and Ca2Nb2O7 (?′ = 38). This can be attributed to the presence of polar nanoregions and the lattice distortion effect in high entropy materials. The appealing dielectric and relaxor behaviour of CSBPN ceramics confirms the efficacy of the high entropy approach to obtain improved properties. 相似文献
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Zhonghua Dai Shengbin Wang Yong Liu Fanbo Zhang Weiguo Liu Xin Zhao Xiangdong Ding Minxia Fang Xiaobing Ren 《Journal of the American Ceramic Society》2023,106(4):2366-2374
Dielectric ceramics with a high recoverable energy density (Wrec) and high efficiency are desirable for the development of pulsed power capacitors under low electric fields. In this study, through the introduction of SrSc0.5Nb0.5O3 into (Bi0.5Na0.5Ti0.95Al0.025Nb0.025O3) [(1-x)BNTA-xSSN], a considerable recoverable energy storage density (Wrec) of approximately 2.7 J/cm3 and energy storage efficiency (η) of approximately 76 % at 210 kV/cm are achieved at x = .1; additionally, η is further improved to 85 % at x = .2. Moreover, η and Wrec of .9BNTA-.1SSN exhibit outstanding stability (thermal and frequency stability) at 150 kV/cm, which is superior to that of other lead-free ceramics. The excellent energy storage performance is attributed to the increased relaxation degree and the formation of ferroelectric nanodomains, whereas the enhanced Eb is ascribed to the increased electrical resistivity and decreased grain size upon modification. These results indicate the potential of (1-x)BNTA-xSSN as an ideal candidate for energy-storage applications. 相似文献
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铌鲜酸铅弛豫型铁电陶瓷的介电老化行为研究 总被引:1,自引:0,他引:1
通过典型弛豫型铁电陶瓷铌镁酸铅介电老化行为的研究,发现高温区的Debye型弛豫过程与介电过程电老现象存在有机联系,指出复合钙钛矿弛豫型电体的结构缺陷特征对其介电老化起着重要作用,介电极化行为与老化行为对比分析和恒温经时老化研究表明,外的局域化电子和空穴对铁电微畴畴壁“钉扎”效应产生失电体介电化行为的快过程。 相似文献
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Microwave Dielectric Properties and Thermally Stimulated Depolarization Currents of (1−x)Ba(Mg1/3Nb2/3)O3–xBaSnO3 Solid Solutions 下载免费PDF全文
Jie Zhang Yuanyuan Zhou Zhenxing Yue Xiaohua Zhang Longtu Li 《Journal of the American Ceramic Society》2015,98(12):3942-3947
Microwave dielectric ceramics of (1?x)Ba(Mg1/3Nb2/3)O3‐xBaSnO3 [(1?x)BMN‐xBS] with high quality factors was synthesized by the solid‐state reaction method. The effects of BaSnO3 additions (x = 0–0.2) on the sinterability, crystal structures, microwave dielectric properties, and microwave dielectric loss mechanisms of BMN were investigated systematically. The degree of 1:2 cation ordering was decreased with increasing Sn content and eventually faded away as x ≥ 0.1, where the low‐temperature relaxations disappeared coincidently through the thermally stimulated depolarization current technique. It was supposed to be the short‐range misplacements of the B‐site cations within the long‐range ordered structure. Meanwhile, the high‐temperature relaxations associated with the in‐grain oxygen vacancies were found in all the title compounds. Though the concentrations of oxygen vacancies of 0.8BMN‐0.2BS were higher than BMN, high Q × f values could also be obtained even in the absence of 1:2 cation ordering. Specifically, the excellent characteristics like εr = 29.02, Q × f = 90 000 GHz and τf = 6.3 ppm/°C were achieved in the specimens of x = 0.2 sintered at 1450°C. 相似文献
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Xiao-Juan He Ling Li Zhong-Shuai Xie Yi-Chi Zhang Ji Zhang Zheng-Bin Gu Haibo Zhang Guoliang Yuan Shan-Tao Zhang 《Journal of the European Ceramic Society》2021,41(4):2435-2442
Solid solution ceramics of (1-x)Sr0.75Ba0.25Nb2O6-xPbZr0.52Ti0.48O3 (x = 0?0.4) were prepared and investigated. The phase evolves from tungsten bronze for x = 0, coexisted tungsten bronze and pyrochlore at x = 0.3, to pyrochlore for x> 0.3. As the results, the ceramics show dramatically composition dependent microstructure and electrical property. The grain shape changes from anisotropic pillar-like with maximum length-diameter ratio of 3.3 at x = 0.2 to isotropic cubic-like for x> 0.2. At the same time, the maximum dielectric constant temperature tends to decrease with an exceptional increase at x = 0.3 due to the coexisted phases. Interestingly, the x = 0.3 ceramic endures ultrahigh breakdown strength of 340 kV/cm, which, together with enhanced polarization, results in maximum recoverable energy storage density of 3.0 J/cm3and energy storage efficiency of 81.5 % at room temperature. 相似文献
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Jialiang Zhang Xing Tian Yong Gao Weizeng Yao Yalin Qin Wenbin Su 《Journal of the American Ceramic Society》2015,98(3):990-995
Domain structure of several poled (K0.50Na0.50)1?xLixNbO3 ceramics (with chemical compositions of x = 0.03, 0.065, and 0.08, respectively) was investigated by means of observing the domain patterns with an acid‐etching technique. Among the three ceramics, the one with x = 0.03 is of orthorhombic phase and the other two are of tetragonal phase at room temperature. It was found that these ceramics possess distinctly different features of domain patterns and show a large difference in the time‐aging stability of piezoelectric properties. For the ceramic with x = 0.03, domain patterns consist of simply one single set or a few sets of parallel stripes inside the polycrystalline grains. In contrast, for those with x = 0.065 or 0.08, herringbone‐type patterns and a large number of watermarks are additionally observed. Furthermore, the ceramic with x = 0.03 was confirmed to have a much better time‐aging stability of piezoelectric properties than the other two. The results indicate that domain structure is more stable in orthorhombic phase than in tetragonal phase. 相似文献