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1.
PbZr0.4Ti0.6O3 dielectric reflectors with large photonic band gap and high average optical reflectivity
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Shi Min Li Gu Jin Hu Chao Wang Wen Chao Zhao Guo Hong Ma Xiao Shuang Chen Jun Hao Chu Ning Dai 《Journal of the American Ceramic Society》2017,100(4):1275-1279
PbZr0.4Ti0.6O3 multilayer, comprising of three PbZr0.4Ti0.6O3 stacks with a slight difference in their periodic thickness, has been designed and fabricated on FTO substrate based on one single chemical solution and on the simple spinning‐coating and annealing technique. The obtained multilayer exhibits a high reflectivity band with 110 nm photonic stop‐band width and average reflectivity of over 80% at room temperature, rendering the novel arrange of PbZr0.4Ti0.6O3 multilayer system a promising candidate as tunable dielectric mirrors, optical cavities and selective filters. 相似文献
2.
《Ceramics International》2021,47(20):28500-28504
The crystal structures and associated energy band structures of classic lead-based PZT (PbZr0.5Ti0.5O3) and lead-free KNN (K0.5Na0.5NbO3) piezoelectric ceramics prepared by a solid-state method are systematically studied based on the First-principles calculations. For better understanding relations between energy band structures and the phase structures in the PbZr0.5Ti0.5O3 and KNN, the components PT (PbTiO3)/PZ (PbZrO3) and KN (KNbO3)/NN (NaNbO3) are also calculated. The results suggest that the vital contribution to R-T morphotropic phase boundary (MPB) in PbZr0.5Ti0.5O3 comes from the hybridization of A-site and B-site ions, which causes stretching and tilting of oxygen octahedron and therefore leads to the formation of R and T phases. The KNN behaves differently. Moreover, it's concluded that the band structure highly inherited from tetragonal PbTiO3 plays an important role in the construction of the R-T phase boundary according to the comparison of PbZr0.5Ti0.5O3 and KNN. In general, the work inspires an idea from the view of energy band structure to realize R-T phase coexistence as well as improved piezoelectric properties in KNN-based lead-free piezoceramics. 相似文献
3.
High‐energy storage density and excellent temperature stability in antiferroelectric/ferroelectric bilayer thin films
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Tiandong Zhang Weili Li Yafei Hou Yang Yu Ruixuan Song Wenping Cao Weidong Fei 《Journal of the American Ceramic Society》2017,100(7):3080-3087
The antiferroelectric/ferroelectric (PbZrO3/PbZr0.52Ti0.48O3) bilayer thin films were fabricated on a Pt(111)/Ti/SiO2/Si substrate using sol‐gel method. PbZr0.52Ti0.48O3 layer acts as a buffered layer and template for the crystallization of PbZrO3 layer. The PbZrO3 layer with improved quality can share the external voltage due to its smaller dielectric constant and thinner thickness, resulting in the enhancements of electric field strength and energy storage density for the PbZrO3/PbZr0.52Ti0.48O3 bilayer thin film. The greatly improved electric breakdown strength value of 2615 kV/cm has been obtained, which is more than twice the value of individual PbZr0.52Ti0.48O3 film. The enhanced energy storage density of 28.2 J/cm3 at 2410 kV/cm has been achieved in PbZrO3/PbZr0.52Ti0.48O3 bilayer film at 20°C, which is higher than that of individual PbZr0.52Ti0.48O3 film (15.6 J/cm3). Meanwhile, the energy storage density and efficiency of PbZrO3/PbZr0.52Ti0.48O3 bilayer film increase slightly with the increasing temperature from 20°C to 120°C. Our results indicate that the design of antiferroelectric/ferroelectric bilayer films may be an effective way for developing high power energy storage density capacitors with high‐temperature stability. 相似文献
4.
《Ceramics International》2022,48(13):18855-18865
The increased demand for ionizing radiation in various fields led to the search for new shielding substances. In this study, five samples of perovskite oxides (BaTiO3, SrTiO3, BaTiO3–SrTiO3, and PbZr0.2Ti0.8O3) doped YBa2Cu3Oy ceramics were prepared to explore their structure and ability for exploitation in the radiation shielding field. The structural properties were explored by using the XRD technique. The XRD results showed an orthorhombic structure for all prepared ceramics. The crystallite size reduces gradually from 96.19 to 66.63 nm with adding different perovskite oxides into the composites. The density shows a variation from about 5.89 to 6.23 g/cm3. The mass attenuation coefficient (MAC) was defined experimentally (MAC)exp and theoretically (MAC)the to check its validity. The maximum relative difference between (MAC)exp and (MAC)the is 7.83%. YBa2Cu3O7/(PbZr0.2Ti0.8O3)2% and YBa2Cu3O7/(BaTiO3–SrTiO3)2% samples showed superior gamma shielding properties and mass stopping power (MSP) for charged particles, respectively, while the pristine YBa2Cu3O7 sample has a better fast neutron removal cross-section (ΣR). From the obtained results, it can be seen a slight variation in shielding properties, indicating the ability to use the different ceramic samples as radiation shielding materials. 相似文献
5.
Origin of low dielectric loss and giant dielectric response in (Nb+Al) co‐doped strontium titanate
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Zichen He Minghe Cao Liang Zhou Lin Zhang Juan Xie Shujun Zhang Junlei Qi Hua Hao Zhonghua Yao Zhiyong Yu Hanxing Liu 《Journal of the American Ceramic Society》2018,101(11):5089-5097
(Nb+Al) co‐doped SrTiO3 ceramics with a nominal composition of Sr(Nb0.5Al0.5)xTi1‐xO3 (x = 0, 0.02, 0.04, and 0.06) were fabricated using the conventional solid‐state reaction method; giant permittivity (10500) and low dielectric loss (0.03) were obtained at x = 0.06. Dielectric and impedance spectroscopy, X‐ray photoelectron spectroscopy, and Raman spectroscopy, were employed to study why the dielectric property improved. The results indicate that the giant dielectric response occurs because of the combined effects of the off‐center Ti3+ reorientation and conduction of electrons with the polar ordering structure Ti3+/Ti4+. In contrast, the low dielectric loss can be attributed to electron localization that occurs because of the defect dipole . These fundamental understandings will benefit the design of doped SrTiO3 ceramics with desired performance. 相似文献
6.
D. Kajewski P. Zajdel A. Soszyński J. Koperski I. Lazar K. Roleder 《Ceramics International》2019,45(8):9871-9877
Lead zirconate-titanate PbZr0.70Ti0.30O3 ceramics doped with bismuth oxide has been investigated. Dielectric and optical measurements were performed to check the dopant influence on phase transitions and pre-transitional effects. It has been postulated that the temperature at which maximum permittivity occurs is not connected with structural phase transitions. 相似文献
7.
Tina Šetinc Matjaž Spreitzer Špela Kunej Janez Kovač Danilo Suvorov 《Journal of the American Ceramic Society》2013,96(11):3511-3517
Polycrystalline sol–gel‐derived SrTiO3/Na0.5Bi0.5TiO3/SrTiO3 (ST/NBT/ST) thin films were designed to achieve the electrical isolation of the NBT, and to mediate the temperature dependency of the dielectric properties. Proper thermal annealing of particulate phase enabled us to achieve compositionally graded elemental profiles between individual ST and NBT layers. The dielectric and ferroelectric properties were investigated with respect to the electrical behavior of the monophasic ST and NBT thin films. The dielectric characteristics of the multilayer thin film were marked by a temperature stable behavior (temperature coefficient of dielectric constant of 780 ppm/°C) in the measured ?50°C to 200°C range, frequency‐independent response at room temperature and improved dielectric loss characteristics compared with the NBT; however, on the expense of decreased permittivity and a reduced ferroelectric stability. Nevertheless, stable dielectric properties were achieved and properties of multilayer may well be exploited in functional devices that demand insensitive operation over wide temperature and frequency ranges. 相似文献
8.
Yongxing Wei Changqing Jin Ruirui Ni Yiming Zeng Dong Gao Zengyun Jian 《Journal of the European Ceramic Society》2018,38(14):4689-4693
In this work, solid solutions of (0.88–x)Bi0.5Na0.5TiO3–0.12BaTiO3– xBa(Ti0.5Ni0.5)O3–δ were designed and prepared. These compositions exhibit ferroelectricity at room temperature, with the tetragonal symmetry. The c/a values are varied from ~1.0067 (x?=?0.1) to ~1.0208 (x?=?0.04). A transition from the high–temperature relaxor state to the low–temperature ferroelectric state is demonstrated by the temperature dependence of dielectric data and Raman spectrum. The direct bandgap decreases from 3.40?eV for x?=?0 to 3.16?eV for x?=?0.1. The Ba(Ti0.5Ni0.5)O3–δ addition leads an additional optical absorption peak in the visible range. The obvious photodielectric effect was discovered. In particular, the relative permittivity of the x?=?0.1 composition rises from ~756 to ~807 under light illumination. 相似文献
9.
High dielectric constant and high‐Q in microwave ceramics of SrTiO3 co‐doped with aluminum and niobium
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Siliang Chen Lingxia Li Shihui Yu Haoran Zheng Zheng Sun 《Journal of the American Ceramic Society》2018,101(5):1835-1840
Al/Nb co‐doped SrTiO3 microwave ceramics with the composition of SrTi1–x(Al0.5Nb0.5)xO3 (x = 0.03, 0.05, 0.1, and 0.15) have been synthesized via a standard solid‐state reaction method. The substitution of (Al0.5Nb0.5)4+ in B‐site inhibits the reduction in Ti4+ ions and the growth of grain size, then the transport of mobile charge carriers is limited, and thus the Q value is improved. For the SrTi0.9(Al0.5Nb0.5)0.1O3 ceramics, in addition to their high dielectric constant (εr ~185), they exhibit correspondingly a high Qf value (~ 9077 GHz) at 2.9 GHz, making the microwave ceramics suitable for myriad device miniaturization and high‐performance wireless communication. 相似文献
10.
Ching‐Chang Chung Chris M. Fancher Catherine Isaac Jason Nikkel Eberhard Hennig Jacob L. Jones 《Journal of the American Ceramic Society》2017,100(9):4352-4361
An electric field loading stage was designed for use in a laboratory diffractometer that enables in situ investigations of the temperature dependence in the field response mechanisms of ferroelectric materials. The stage was demonstrated by measuring PbZr1?xTixO3 (PZT) based materials—a commercially available PZT and a 1% Nb‐doped PbZr0.56Ti0.44O3 (PZT 56/44)—over a temperature range of 25°C to 250°C. The degree of non‐180° domain alignment (η002) of the PZT as a function of temperature was quantified. η002 of the commercially available PZT increases exponentially with temperature, and was analyzed as a thermally activated process as described by the Arrhenius law. The activation energy for thermally activated domain wall depinning process in PZT was found to be 0.47 eV. Additionally, a field‐induced rhombohedral to tetragonal phase transition was observed 5°C below the rhombohedral‐tetragonal transition in PZT 56/44 ceramic. The field‐induced tetragonal phase fraction was increased 41.8% after electrical cycling. A large amount of domain switching (η002=0.45 at 1.75 kV/mm) was observed in the induced tetragonal phase. 相似文献
11.
Microstructure Evolution of In Situ Pulsed‐Laser Crystallized Pb(Zr0.52Ti0.48)O3 Thin Films
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Adarsh Rajashekhar Huai‐Ruo Zhang Bharadwaja Srowthi Ian M. Reaney Susan Trolier‐McKinstry 《Journal of the American Ceramic Society》2016,99(1):43-50
Integration of lead zirconate titanate (PZT) films with temperature‐sensitive substrates (CMOS, polymers) would benefit from growth at substrate temperatures below 400°C. In this work, in situ pulsed‐laser annealing [Rajashekhar et al. (2013) Appl. Phys. Lett., 103 [3] 032908] was used to grow crystalline lead zirconate titanate (PbZr0.52Ti0.48O3) thin films at a substrate temperature of ~370°C on PbZr0.30Ti0.70O3‐buffered platinized silicon substrates. Transmission electron microscopy analysis indicated that the films were well crystallized into columnar grains, but with pores segregated at the grain boundaries. Lateral densification of the grain columns was significantly improved by reducing the partial pressure of oxygen from 120 to 50 mTorr, presumably due to enhanced adatom mobility at the surface accompanying increased bombardment. It was found that varying the fractional annealing duration with respect to the deposition duration produced little effect on lateral grain growth. However, increasing the fractional annealing duration led to shift of 111 PZT X‐ray diffraction peaks to higher 2θ values, suggesting residual in‐plane tensile stresses in the films. Thermal simulations were used to understand the annealing process. Evolution of the film microstructure is described in terms of transient heating from the pulsed laser determining the nucleation events, while the energy of the arriving species dictates grain growth/coarsening. 相似文献
12.
Wei Huang Riad Nechache Shun Li Mohamed Chaker Federico Rosei 《Journal of the American Ceramic Society》2016,99(1):226-233
We report a systematic study of the electrical and optical properties of epitaxial perovskite p‐type In‐doped SrTiO3 thin films (SrInxTi1?xO3, 0 ≤ x ≤ 0.15) grown on single‐crystal (100)‐oriented LaAlO3 substrates using a hybrid method which combines pulsed laser deposition and molecular beam epitaxy in a range of deposition conditions. X‐ray diffraction analysis confirms the epitaxial growth of high crystal quality films. Four‐point probe and Hall Effect measurements demonstrate that the films are p‐type semiconductors with a low resistivity of ~10?2 Ω·cm and a high carrier concentration of ~1019 cm?3. The optical transmittance spectra reveal that the films are highly transparent (?70%) in the visible region. 相似文献
13.
Meysam Sharifzadeh Mirshekarloo Chee Kiang Ivan Tan Yang Li Szu Cheng Lai Lei Zhang Ten It Wong Mojtaba Rahimabadi Kui Yao Ganesh Shankar Samudra 《Journal of the American Ceramic Society》2016,99(4):1429-1434
Controllable phase transformation between antiferroelectric (AFE) and ferroelectric (FE) states suggests multifunctional properties valuable for many device applications. Compared to AFE bulk ceramics with large voltage required for driving electric field‐induced phase transition, implementation of structures comprising multiple thin AFE ceramic layers can realize applications by reducing the switching operation voltage in the feasible range. Here, it is found that a compressive residual stress is developed in multilayer (Pb0.97,La0.02)(Zr0.66,Snx,Ti0.34?x)O3 (PLZST) ceramic co‐fired with multiple Pd/Ag electrode layers, and the compressive residual stress can stabilize AFE phase. AFE phase forms in the PLZST multilayer ceramic with composition corresponding to FE in the bulk materials. Thermodynamic analysis based on free energy of FE and AFE phases well explains the FE to AFE phase transformation observed in the multilayer ceramic under the compressive stress. The findings exhibit a new strategy to tune structure and functional properties of multilayer ceramics through stress engineering for achieving device applications. 相似文献
14.
Jianwei Zhao Stephen D. Funni Emily R. Molina Elizabeth C. Dickey Jacob L. Jones 《Journal of the European Ceramic Society》2021,41(6):3357-3362
In situ high-energy X-ray diffraction (XRD) was performed on lead-zirconate-titanate-based ferroelectric materials with composition near the morphotropic phase boundary (MPB). The utilization of the two-dimensional area detector in in situ field-dependent experiments enables the complete analysis of the material response with respect to all azimuthal angles at each field amplitude. The studies reveal that the field-induced phase transition from tetragonal to rhombohedral is dependent on crystal orientation in Nb-doped PbZr0.53Ti0.47O3 that is in close compositional proximity to the MPB. However, only domain wall motion is activated in Nb-doped PbZr0.50Ti0.50O3, which is further in composition from the MPB. This synchrotron-based XRD characterization approach illustrates the importance in evaluating the orientation-dependence of phase transitions in piezoelectric and ferroelectric polycrystalline materials. 相似文献
15.
《Ceramics International》2023,49(7):10864-10870
PbTi1-xZrxO3 (PZT) thin films prepared by sol-gel method have paid much attention due to the excellent performances in piezoelectric, dielectric, ferroelectric and electro-optical. However, the high crystallization temperature of the PZT thin films restricts the compatibility with modern COMS technology. In this work, PbZr0.52Ti0.48O3 (PZT) ferroelectric thin films were successfully prepared by sol-gel method at an ultra-low temperature (~450 °C) in an oxygen plasma-assisted environment. A large spontaneous polarization ~30 μC/cm2 and a large dielectric breakdown ~2,900 kV/cm were obtained in the sample annealed at 450 °C for 25 h. We believe that the oxygen plasma-assisted ultra-low temperature (OPAULT) annealing process is a promising way for the sol-gel technology applied in the modern COMS devices. 相似文献
16.
Xiaokuo Er Fei Shao Sizhe Diao Hongliang Wang Qinghua Ma Pingping Liu Jinxing Zhang Qian Zhan 《Journal of the European Ceramic Society》2021,41(11):5512-5518
The integration units with functional and structural material components have been developed largely recently. In the present study, 200 nm-thick polycrystalline PbZr0.52Ti0.48O3 (PZT) films with a dense columnar structure were grown on LaNiO3 (LNO) buffered heat-resistant steel substrates via a low-cost chemical solution approach. The behavior of the functional PZT films when combined with the structural steel was investigated mainly by TEM and electrical measurement. A large in-plane compressive stress was obtained in the PZT films due to the thermal expansion mismatch of about 88.2 % between the thin films and the steel substrates, which intensifies the orientation of the films toward c-axis. Sub-10 nm 90° nanodomains were alternately distributed in [001] grains which is beneficial to the piezoelectric performance, and the equivalent d33 value is ~44.4 pm V?1. A remnant polarization (Pr) of ~67.3μC/cm2 and a dielectric constant of ~425 were obtained. The enhanced electrical properties are associated with the stress-induced improved c-axis spontaneous polarization and crystal orientation in the hybrid system. This work may provide a theoretical basis for further integrating functional elements into metallic materials, which is valuable for covering the gap between academic research and industrial mass production. 相似文献
17.
SrLa(R0.5Ti0.5)O4 (R=Mg,Zn) microwave dielectric ceramics with complex K2NiF4‐type layered perovskite structure
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Dense SrLa(R0.5Ti0.5)O4 (R=Mg, Zn) ceramics were prepared by a standard solid‐state reaction method. The single phase with complex K2NiF4‐type layered perovskite structure and I4/mmm space group was revealed by XRD, and the refined structure was analyzed by Rietveld analysis. Significantly improved dielectric constant was obtained in SrLa(R0.5Ti0.5)O4 ceramics compared to the analogues SrLaAlO4 and SrLaGaO4, which is attributed to the increasing normalized bond lengths of Sr/La‐O(1) and Sr/La‐O(2a) bonds and the higher polarizability of (R0.5Ti0.5)3+ than Al3+ and Ga3+. In addition, τf converts to a positive value with the increase in dielectric constant. The following microwave dielectric properties were obtained in the dense ceramics: εr=25.5, Qf=72 000 GHz, τf=29 ppm/°C for SrLa(Mg0.5Ti0.5)O4, and εr=29.4, Qf=34 000 GHz, τf=38 ppm/°C for SrLa(Zn0.5Ti0.5)O4. Furthermore, the stability of K2NiF4‐type structure in MLnBO4 [M=Ca, Sr, Ba; Ln=Y, Sm, Nd, La; B=Al, Ga, (Mg0.5Ti0.5), (Zn0.5Ti0.5)] compounds was discussed in relation to the tolerance factor of perovskite layer and the radius ratio of M2+ and Ln3+, based on which near‐zero τf values are expected to be obtained in SrLa(R0.5Ti0.5)O4‐SrLaAlO4 and SrLa(R0.5Ti0.5)O4–SrLaGaO4 unlimited solid solutions. 相似文献
18.
Effect of Mechanical Constraint on Domain Reorientation in Predominantly {111}‐Textured Lead Zirconate Titanate Films
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Giovanni Esteves Margeaux Wallace Raegan Johnson‐Wilke Chris M. Fancher Rudeger H. T. Wilke Susan Trolier‐McKinstry Jacob L. Jones 《Journal of the American Ceramic Society》2016,99(5):1802-1807
Ferroelectric/ferroelastic domain reorientation was measured in 2.0 μm thick tetragonal {111}‐textured PbZr0.30Ti0.70O3 thin films using synchrotron X‐ray diffraction (XRD). Lattice strain from the peak shift in the 111 Bragg reflection and domain reorientation were quantified as a function of applied electric field amplitude. Domain reorientation was quantified through the intensity exchange between the 112 and 211 Bragg reflections. Results from three different film types are reported: dense films that are clamped to the substrate (as‐processed), dense films that are partially released from the substrate, and films with 3% volume porosity. The highest amount of domain reorientation is observed in grains that are misoriented with respect to the {111} preferred (domain engineered) orientation. Relative to the clamped films, films that were released from the substrate or had porosity exhibited neither significant enhancement in domain reorientation nor in 111 lattice strain. In contrast, similar experiments on {100}‐textured and randomly oriented films showed significant enhancement in domain reorientation in released and porous films. Therefore, {111}‐textured films are less susceptible to changes in properties due to mechanical constraints because there is overall less domain reorientation in {111} films than in {100} films. 相似文献
19.
Low‐Temperature Dielectric Relaxations Associated with Mixed‐Valent Structure in Na0.5Bi0.5Cu3Ti4O12
Xiaohong Sun Chunchang Wang Guojing Wang Changmei Lei Teng Li Lina Liu 《Journal of the American Ceramic Society》2013,96(5):1497-1503
We, herein, present comparative investigations on the Na0.5Bi0.5Cu3Ti4O12 ceramic samples with and without 10 mol% excess of Na/Bi. The samples were prepared by the standard solid‐state reaction technique. The dielectric properties of the sample were investigated in the temperature (93–320 K) and frequency (20 Hz–10 MHz) windows. Three thermally activated dielectric relaxations observed in Na0.5Bi0.5Cu3Ti4O12 with the activation energies of 0.104, 0.267, and 0.365 eV for the low‐, middle‐, and high‐temperature dielectric relaxations, respectively. Only the low‐temperature relaxation was observed in both Na and Bi excessive samples. X‐ray photoemission spectroscopy results revealed the mixed‐valent structures of Cu+/Cu2+ and Ti3+/Ti4+ in Na0.5Bi0.5Cu3Ti4O12 sample, but only Ti3+/Ti4+ in Na and Bi excessive samples. Our results showed that the dielectric properties of the investigated samples are strongly linked with these mixed‐valent structures. The high‐ and low‐temperature relaxations were attributed to be a polaron‐type relaxation due to localized carriers hopping between Cu+/Cu2+ and Ti3+/Ti4+, respectively. The middle‐temperature relaxation is suggested to be a dipole‐type relaxation caused by the defect complex of bismuth and oxygen vacancies. 相似文献
20.
《Journal of the European Ceramic Society》2006,26(6):897-900
PZT thick films (PbZr0.53Ti0.47O3 with the addition of 6% PbO and 2% Pb5Ge3O11) with a low sintering temperature were printed and fired on LTCC substrates (951, Du Pont), covered with an alumina barrier layer. The electrical characteristics (remanent polarisation, coercive field, dielectric constant and dielectric loss) of these PZT thick films, together with sets prepared on “unprotected” LTCC substrates and on alumina substrates were compared. Whereas the electrical characteristics of the films on LTCC substrates deteriorated significantly due to interactions between the LTCC substrates and the PZT layers the values obtained for the LTCC/alumina barrier structures were comparable with those on ceramic alumina substrates. 相似文献