5,329 results on '"*LEAD titanate"'
Search Results
2. Tailoring perovskite ceramics for improved structure, vibrational behaviors and radiation protection: The role of lanthanum in PbTiO3
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Almousa, N., Issa, Shams A. M., Salem, M.M., Darwish, Moustafa A., Serag, Eman N., Nazrin, S.N., and Zakaly, Hesham M. H.
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- 2024
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3. Interfacial strain induced giant magnetoresistance and magnetodielectric effects in multiferroic BCZT/LSMO thin film heterostructures.
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Chatterjee, Subhashree, Yadav, Kusampal, Mondal, Nasiruddin, Kumar, Ganga S., Bhattacharya, Dipten, and Mukherjee, Devajyoti
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THIN films , *GIANT magnetoresistance , *MAGNETORESISTANCE , *FERROELECTRIC thin films , *HETEROSTRUCTURES , *UNIT cell , *PULSED laser deposition , *LEAD titanate , *BARIUM titanate - Abstract
Layered thin films of the ferroelectric perovskite Ba0.85Ca0.15Ti0.9Zr0.1O3 (BCZT) and the ferromagnetic half-metal La0.80Sr0.20MnO3 (LSMO) are well-known multiferroic systems that show promise for spintronic applications. In this work, the structure–property relationships are explored in novel BCZT/LSMO thin film heterostructures with optimized ferroic properties. Epitaxial BCZT/LSMO thin film heterostructures are grown by varying the lattice mismatch strains on single crystal LaAlO3 (LAO) (100) and MgO (100) substrates using the pulsed laser deposition technique. The epitaxial strain in the films gives rise to a tetragonal distortion of the BCZT and LSMO unit cells and significantly affects their magnetotransport and magnetodielectric properties. The BCZT/LSMO/LAO heterostructure exhibits a colossal magnetoresistance effect due to a large out-of-plane tensile strain, which induces enhanced carrier hopping in the LSMO layer as compared to the BCZT/LSMO/MgO film. The larger tetragonal distortion of the BCZT unit cell in BCZT/LSMO/MgO contributes to higher dielectric permittivity, with a greater dielectric maxima temperature and freezing temperature. Magnetodielectric measurements reveal a hitherto unobserved giant magnetodielectric effect in the BCZT/LSMO/MgO film, attributed to a large in-plane strain, which induces interfacial polarization distortion at the interfacial layer. Overall, this work elucidates the unique strain and charge-mediated cross-coupled phenomena of magnetic and electric orders in multiferroic thin film heterostructures, which are critical for their technological applications. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Thermal cycle stability and microstructure of Pb(Mg1/3Nb2/3)O3-PbTiO3 single crystals.
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Liang, Min, Xiong, Ruibin, Chen, Shuli, Wang, Zujian, Su, Bin, Su, Rongbing, Liu, Ying, and He, Chao
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SINGLE crystals , *THERMOCYCLING , *THERMAL stability , *FERROELECTRIC crystals , *PERMITTIVITY , *LEAD titanate - Abstract
The Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) ferroelectric single crystals have been commercially available as important components in medical ultrasound transducers due to their excellent piezoelectric and electromechanical coupling performance. The variation in piezoelectric and dielectric properties of PMN-PT single crystals with ambient temperature is an important application indicator. In this work, the PMN-PT single crystals after direct current poling (DCP) and alternating current poling (ACP) were subjected to the cyclic thermal treatment process. The thermal cycling stability and microstructural changes in PMN-PT single crystals were investigated. The ACP single crystals exhibit a higher dielectric constant ε 33 T / ε 0 (6500–7600) and piezoelectric coefficient d33 (2100–2500 pC N−1) compared to the DCP single crystals (ε 33 T / ε 0 of 4100–5000, d33 of 1200–1300 pC N−1). Under thermal cycling at 60 °C, the DCP and ACP single crystals exhibit good thermal cycling stability after 150 cycles. Microstructural observations show that the domain structure of the DCP single crystals exhibits "staggered domain walls, inhomogeneous domain size, variety of domain structure," while the relatively homogeneous stripe-like domains were observed in the ACP single crystals. After thermal cycling, new fine striped domains appear in both the DCP and ACP single crystals due to the instability of rotated polarization, but the piezoelectric and dielectric properties are not greatly affected. This work provides an intensive understanding of the effects of thermal cycling on the domain structure, which is useful for applications. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Phase-field theory study on the modulation mechanism of oxygen vacancy concentration on charged domain wall in ferroelectric thin films.
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Zhu, Bingyan, Yang, Wanting, Deng, Yuhui, Yang, Qiong, Jiang, Jie, and Jiang, Limei
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FERROELECTRIC thin films , *PHOTOVOLTAIC effect , *MODULATION theory , *LEAD titanate , *BARIUM titanate , *OXYGEN , *ELECTRIC fields - Abstract
This study analyzes the regulatory mechanism of oxygen vacancy concentration on tail-to-tail charged domain walls (T–T CDWs), along with the writing time, conduction current magnitude, and retention performance of through-type T–T CDWs. The research results show that the highest density and length of T–T CDWs are achieved when the oxygen vacancy concentration is 1 × 1020 cm−3. Moreover, the successful writing of through-type T–T CDWs is limited to a certain electric field range, which is controlled by oxygen vacancy concentration. An increase in the oxygen vacancy concentration leads to a decrease in the maximum and minimum threshold electric fields required for writing through-type charged domain walls. The writing time and conductivity of through-type T–T CDWs determine the information writing speed and signal strength of domain wall memories, and the oxygen vacancy concentration also plays a regulatory role in both aspects. When the oxygen vacancy concentration is 1 × 1020 cm−3, the through-type T–T CDW exhibits the fastest writing speed, requiring only 8 ns. The magnitude of the conduction current of through-type T–T CDWs is directly proportional to the oxygen vacancy concentration. The through-type T–T CDWs formed by the aggregation of oxygen vacancies exhibit excellent retention performance, making them highly promising for applications in ferroelectric domain wall memories. Our research demonstrates that oxygen vacancies have a significant regulatory effect on the morphology and current response of charged domain walls, opening up new avenues for the study of domain wall memories. [ABSTRACT FROM AUTHOR]
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- 2024
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6. A phenomenological thermodynamic energy density function for ferroelectric wurtzite Al1−xScxN single crystals.
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Gu, Yijia, Meng, Andrew C., Ross, Aiden, and Chen, Long-Qing
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ENERGY function , *ENERGY density , *SINGLE crystals , *WURTZITE , *PHASE transitions , *LEAD titanate , *BARIUM titanate - Abstract
A Landau–Devonshire thermodynamic energy density function for ferroelectric wurtzite aluminum scandium nitride (Al1−xScxN) solid solution is developed. It is parametrized using available experimental and theoretical data, enabling the accurate reproduction of composition-dependent ferroelectric properties, such as spontaneous polarization, dielectric permittivity, and piezoelectric constants, for both bulk and thin films. The maximum concentration of Sc for the wurtzite structure to remain ferroelectric is found to be 61 at. %. A detailed analysis of Al1−xScxN thin films reveals that the ferroelectric phase transition and properties are insensitive to substrate strain. This study lays the foundation for quantitative modeling of novel ferroelectric wurtzite solid solutions. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Piezoelectric energy harvester with outstanding output performance at low frequency vibration based on concentrating force on the piezoelectric element by parallel springs.
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Hao, Yifan, Luo, Hongzhi, Lu, Xinyue, Huang, Jiawei, Chen, Hang, and Yang, Tongqing
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FREQUENCIES of oscillating systems , *PIEZOELECTRIC ceramics , *STAINLESS steel , *LEAD titanate , *LEAD zirconate titanate - Abstract
This paper proposes a piezoelectric energy harvester that concentrates force on the piezoelectric element by parallel springs. When vibrating, the force exerted by the mass is released at three equal points on the surface of the brass substrate through three parallel springs. This concentrated release of energy through the spring amplification effect facilitates large deformation of the piezoelectric ceramic sheet, resulting in a higher charge output. The results show that under the combined action of a 14 g annular hollow mass and a 0.3 mm wire diameter stainless steel spring, the energy harvester based on the lead zirconate titanate ceramic exhibited an outstanding output power of 1.0–32.1 mW at a low resonance frequency with acceleration amplitudes of 0.5–3 g (1 g = 9.8 m/s2). More importantly, to match the vibration frequency of the actual environment, this paper optimized the structure of the harvester and proposed that the harvester can be designed by selecting the weight of the mass block, the parameters and number of springs, and the shape of the brass substrate. The energy harvester designed in this study is expected to capture energy from low-frequency natural environments and exhibit outstanding output performance, which can provide guidelines for future efforts in this direction. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Field dependence of the electrocaloric effect in BaTiO3 and Ba(Zr0.12Ti0.88)O3: High-resolution measurements around the phase transition.
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Fischer, J., Molin, C., Gebhardt, S. E., Hägele, D., and Rudolph, J.
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PYROELECTRICITY , *PHASE transitions , *FIRST-order phase transitions , *DIELECTRIC measurements , *CURIE temperature , *LEAD titanate - Abstract
The electric field dependence of the electrocaloric effect is investigated in BaTiO 3 and Ba(Zr 0.12 Ti 0.88 )O 3 by a direct method with sub-mK temperature resolution. The field dependence of the caloric temperature change Δ T (E) shows a pronounced change within a few Kelvin around the Curie temperature for the first-order phase transition in BaTiO 3. The transition from a linear field dependence in the ferroelectric phase over a butterfly-shaped to a quadratic field dependence in the paraelectric phase is compared to predictions of Landau–Devonshire theory. The simultaneous measurement of caloric and dielectric properties further allows for the investigation of the polarization dependence Δ T (P) of the electrocaloric effect. We find clear deviations from the predicted quadratic polarization dependence for temperatures close to the Curie temperature. Ba(Zr 0.12 Ti 0.88 )O 3 shows in contrast only a slow and gradual change of the field dependence over a broad temperature range as a consequence of its diffuse phase transition. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Dynamics of polarization loss and imprint in bilayer ferroelectric tunnel junctions.
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Barbot, J., Fontanini, R., Segatto, M., Coignus, J., Triozon, F., Carabasse, C., Bedjaoui, M., Andrieu, F., Esseni, D., and Grenouillet, L.
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ALUMINUM oxide , *LEAD titanate - Abstract
This paper presents polarization loss and imprint in bilayer ferroelectric tunnel junctions as a function of relaxation time (< 1 s) and after different SET/RESET pulses. Measurements were performed on Hf 0.5 Zr 0.5 O 2 /Al 2 O 3 stack at room temperature and systematically compared to reference samples without Al 2 O 3. The experimental results were interpreted using self-consistent simulations coupling the polarization dynamic with charge trapping at the FE/DE interface. From this, mechanisms playing on short-term retention and imprint were explained dynamically. Amount of trapped charge modulated by amplitude and duration of SET/RESET pulses was presented as a root cause. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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10. Microstructure and Properties of a Glass-Fiber Composite as a Function of the Specific Surface Area of the Lead Titanate Filler.
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Udinceva, Ya. E., Spiridonov, Yu. A., and Sigaev, V. N.
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LEAD titanate , *CRYSTAL glass , *THERMAL expansion , *SURFACE area , *MICROSCOPY - Abstract
Influence of the specific surface area and filler concentration on the coefficient of linear thermal expansion (CLTE) of sintered composites based on high lead fused glass and lead titanate was investigated in order to obtain solder materials offering unusually low CLTE values. The microstructure of compositions was investigated by optical microscopy methods in combination with birefringence testing with a localization of about 1 μm. In samples containing up to 55% PbTiO3 powder having a specific surface area of less than 560 cm2/g, near-zero and even negative values have been achieved. [ABSTRACT FROM AUTHOR]
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- 2025
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11. A Bandgap‐Tuned Tetragonal Perovskite as Zero‐Strain Anode for Potassium‐Ion Batteries.
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Yang, Weijia, Huang, Jun, Zheng, Qinfeng, Chen, Liwei, Orita, Akihiro, Saito, Nagahiro, Zhang, Zhengxi, Zhang, Yixiao, and Yang, Li
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ENERGY storage , *POWER resources , *LEAD titanate , *BAND gaps , *ENERGY density - Abstract
PIBs are emerging as a promising energy storage system due to high abundance of potassium resources and theoretical energy density, however, progress of PIBs is severely hindered by structural instability and poor cycling of anode material during continual insertion and extraction of larger‐sized K+. Hence, developing anode material with structural stability and stable cycling remains a great challenge. Herein, band gap‐tuned Mo‐doped and carbon‐coated lead titanate (CMPTO) with zero‐strain K+ storage is presented as ultra‐stable PIBs anode. Mo doping introduces narrowed band gap and optimized crystal lattice for enhanced intrinsic electron and ion transfer. Demonstrated by in situ XRD characterizations, the crystal structure stays stable with unchanged peak positions, fully revealing zero‐strain characteristic of CMPTO anode during potassium storage for stable cyclic capability. Ultimately, CMPTO anode achieved ultra‐stable cycling performance of 7000 cycles at 500 mA g−1 with high capacity retention of 90 % and considerable specific capacity of 130.9 mAh g−1 after 600 cycles at 100 mA g−1; with relatively large density, CMPTO realized eminent volumetric capacity of 1111.09 mAh cm−3 and ultra‐long cycling life of 10000 cycles at 7041 mA cm−3. This work introduces a promisingly new route into developing anode materials with ultra‐stable performance for PIBs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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12. Numerical Study of 2D Nanomaterial-Based Surface Plasmon Resonance Biosensor.
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Jaiswal, Laxmi, Dwivedi, D. K., Lohia, Pooja, Mishra, Adarsh Chandra, Yadav, Sapana, and Yadav, R. K.
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SURFACE plasmon resonance , *LEAD titanate , *ZINC oxide , *TRANSFER matrix , *ELECTRIC fields - Abstract
The extant work exhibits a unique design of surface plasmon resonance (SPR) which has been suggested for indications of different malarial disease stages. The device construction is founded on the Kretschmann configuration and consists of multiple layers, including BK7 prism, silver (Ag) metal layer, zinc oxide (ZnO), lead titanate (PbTiO3), and a heterostructure 2D nanomaterial (black phosphorus; BP) at the top. The angular reflectivity is evaluated using TMM stands for transfer matrix method. The thickness and number of layers have been studied for the optimization of sensitivity. Additionally, normalized electric field distribution, electric field intensity enhancement factor, and phase interrogation parameters have been applied to validate the position of occurrence of resonance angle and ultrahigh sensitivity. The equivalent angular sensitivity for the refractive indices of different stages of malaria infection (ring stage, trophozoite stage, and schizont stage) are 1.396, 1.381, and 1.371 for which the angular sensitivity is 387°/RIU, 305°/RIU, and 273°/RIU respectively. The suggested SPR sensor performs transcendentally when it comes to ring stage detection and corresponding quality factor of 107.12RIU-1 and detection accuracy of 0.27 deg-1. The sensor design can be crucial for future adavncement and practical implimentation of biosensors. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Crystallite size and phase purity in Pb1-xSrxTiO3 ferroelectric perovskites for biomedical applications via controlled sintering.
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Widodo, Rahmat Doni, Anis, Samsudin, Fitriyana, Deni Fajar, Manawan, Maykel, Sah, Joni, Santiko, Aji, Bin Mamat, Rizalman, Yusuf, Abdulfatah Abdu, and Ammarullah, Muhammad Imam
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LEAD titanate ,STRONTIUM titanate ,FERROELECTRIC materials ,CURIE temperature ,CRYSTAL growth - Abstract
Lead strontium titanate (Pb
1-x Srx )TiO3 (PST) is a ferroelectric perovskite material with tunable properties, including Curie temperature, spontaneous polarization, and high dielectric permittivity, making it promising for advanced biomedical applications, such as biosensors, bioimaging, and light-activated therapeutics. This study investigates the effect of varying sintering temperatures on the crystallite size and phase purity of PST, aiming to optimize its performance for biomedical devices. PbCO3 , SrCO3 , and TiO2 powders were processed via ball milling for 58 hours, followed by sintering at temperatures ranging from 500°C to 1100°C. Laser diffraction particle size analysis and X-ray diffraction (XRD) were used to assess the particle size and crystal phase transformations. The results demonstrate that higher sintering temperatures improve the PST phase composition, reducing impurities and enhancing crystallite growth. The most significant crystal growth was observed at 900°C, while the optimal phase purity and crystallite size (91.5 nm) were achieved at 1100°C, producing 100% single-phase PST. These findings emphasize the critical role of sintering temperature in tailoring PST's properties, enhancing its suitability for electronic and microelectronic biomedical devices. Controlled sintering in perovskite materials opens new pathways for their application in medical diagnostics and therapeutic technologies. [ABSTRACT FROM AUTHOR]- Published
- 2024
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14. Understanding the stress effect of TiN top electrode on ferroelectricity in Hf0.5Zr0.5O2 thin films.
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Han, Runhao, Hong, Peizhen, Zhang, Bao, Bai, Mingkai, Hou, Jingwen, Yang, Jinchuan, Xiong, Wenjuan, Yang, Shuai, Gao, Jianfeng, Lu, Yihong, Liu, Fei, Luo, Feng, and Huo, Zongliang
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THIN films , *TITANIUM nitride , *FERROELECTRICITY , *LEAD titanate , *ELECTRODES , *PHASE transitions , *GRAIN size - Abstract
We conducted a comprehensive investigation on the influence of TiN thickness and stress on the ferroelectric properties of Hf 0.5 Zr 0.5 O 2 thin films. TiN top electrode layers with varying thicknesses of 2, 5, 10, 30, 50, 75, and 100 nm were deposited and analyzed. It was observed that the in-plane tensile stress in TiN films increased with the thickness of the TiN top electrode. This is expected to elevate the tensile stress in the Hf 0.5 Zr 0.5 O 2 film, consequently leading to an enhancement in ferroelectric polarization. However, the effect of stress on the ferroelectric behavior of Hf 0.5 Zr 0.5 O 2 films exhibited distinct stages: improvement, saturation, and degradation. Our study presents novel findings revealing a saturation and degradation phenomenon of in-plane tensile stress on the ferroelectric properties of polycrystalline Hf 0.5 Zr 0.5 O 2 films, thereby partially resolving the discrepancies between experimental observations and theoretical predictions. The observed phase transformation induced by tensile stress in Hf 0.5 Zr 0.5 O 2 films played a crucial role in these effects. Furthermore, we found that the impact of the TiN top electrode thickness on other factors influencing ferroelectricity, such as grain size and oxygen vacancies, was negligible. These comprehensive results offer valuable insights into the influence of stress and TiN top electrode thickness on the ferroelectric behavior of Hf 0.5 Zr 0.5 O 2 films. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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15. Realizing tunneling electroresistance effect in the Au/h-BN/In2Se3/Au vertical ferroelectric tunnel junction.
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Yang, Shuli, Kang, Lili, Zheng, Xiaohong, Jiang, Peng, and Zhao, Gaofeng
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TUNNEL junctions (Materials science) , *FERROELECTRIC materials , *GREEN'S functions , *FERROELECTRIC devices , *TUNNEL design & construction , *DENSITY functional theory , *LEAD titanate - Abstract
Two-dimensional (2D) ferroelectric tunnel junctions (FTJs) have great potential in the design of non-volatile memory devices due to the tunneling electroresistance (TER) effect and the fact that it is not constrained by critical thickness. Incorporation of 2D ferroelectric materials in realistic FTJs inevitably involves the contacts to the traditional three-dimensional (3D) metals. However, how to design the FTJs by combining the 2D ferroelectric materials with the 3D metals still needs to be studied. In this work, we design a vertical 3D FTJ by adopting the 3D metal Au as the left and right electrodes and the 2D ferroelectric material In2Se3 together with h-BN as the central scattering region. By density functional theory combined with the non-equilibrium Green's function (NEGF) method, we demonstrate that the h-BN intercalation with a large bandgap plays the role of good "insulator," which breaks the symmetry of the left and right electrodes. As a result, we obtain the TER ratio of about 170%, and it can be further improved to about 1200% if two layers of In2Se3 (2L-In2Se3) are adopted as the tunneling barrier layer. Our results provide another way for the design and application of ferroelectric memory devices based on 2D ferroelectric materials. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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16. Phase-field simulations of polarization variations in polycrystalline Hf0.5Zr0.5O2 based MFIM: Voltage dependence and dynamics.
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Koduru, Revanth, Ahmed, Imtiaz, Saha, Atanu K., Lyu, Xiao, Ye, Peide, and Gupta, Sumeet K.
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VOLTAGE , *HIGH voltages , *LEAD titanate , *POLYCRYSTALLINE silicon - Abstract
In this work, we investigate the device-to-device variations in the remanent polarization of metal–ferroelectric–insulator–metal stacks based on ferroelectric hafnium–zirconium–oxide (HZO). Our study employs a 3D dynamic multi-grain phase-field model to consider the effects of the polycrystalline nature of HZO in conjunction with the multi-domain polarization switching. We explore the dependence of variations on various design factors, such as the ferroelectric thickness and voltage stimuli (set voltage, pulse amplitude, and width), and correlate the trends to the underlying polarization switching mechanisms. Our analysis reveals a non-monotonic dependence of variations on the set voltage due to the coupled effect of the underlying polycrystalline structure variations and the voltage dependence of polarization switching mechanisms. We further report that collapsing of oppositely polarized domains at higher set voltages can lead to an increase in variations, while ferroelectric thickness scaling lowers the overall device-to-device variations. Considering the dynamics of polarization switching, we highlight the key role of voltage and temporal dependence of domain nucleation in dictating the trends in variations. Finally, we show that using a lower amplitude pulse for longer duration to reach a target mean polarization state results in lower variations compared to using a higher amplitude pulse for shorter duration. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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17. Bandgap engineered BaTiO3-based ferroelectric oxides for photovoltaic applications.
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Sarath, N. V., Chauhan, Amit, Bidika, Jatin Kumar, Pal, Subhajit, Nanda, B. R. K., and Murugavel, P.
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LEAD titanate , *PHOTOVOLTAIC effect , *FERROELECTRIC materials , *OPEN-circuit voltage , *DENSITY functional theory , *HYSTERESIS loop , *OXIDES - Abstract
Ferroelectric oxides have gained research attention in the field of ferroelectric photovoltaics (PV) after the discovery of power conversion efficiency exceeding the Shockley–Queisser limit in BaTiO3 (BTO) crystals. However, advancement in this field is hindered by the wide bandgap (>3 eV) nature of ferroelectric oxides. In this work, a novel lead-free ferroelectric (1 − x)BTO − xBi(Ni2/3Nb1/3)O3 system was proposed and demonstrated to show bandgap reduction without compromising the polarization. Notably, the system displayed a bandgap reduction from 3.1 to 2.4 eV upon varying the composition from x = 0.0 to 0.05. Particularly, the optimal composition x = 0.02 showed enhancement in polarization (Pmax = 16 μC/cm2) and anomalous PV response with an open-circuit voltage of 6 V at 300 K. The origin of the bandgap reduction and polarization retention is explored experimentally by Raman spectroscopic measurements and analyzed theoretically by density functional theory. Our results revealed that the oxygen octahedral distortions and Ni2+ doping favor bandgap lowering, and Bi3+ ions stabilize the ferroelectric polarization. This study provides insight into the origin of bandgap tuning and paves the route for exploring new low-bandgap ferroelectric material with room temperature polarization. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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18. On Flexoelectricity in a Multidomain Ferroelectric.
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Yurkov, A. S. and Yudin, P. V.
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PERTURBATION theory , *LEAD titanate , *PIEZOELECTRICITY - Abstract
Flexoelectricity in a macroscopically unpolarized multidomain ferroelectric is considered. It has been shown that the flexoelectric moduli are modified due to the piezoelectric effect in individual domains. The perturbation theory has been developed, where the effect appears in the third order. The estimate of the effect for lead titanate in the isotropic approximation has shown that corrections to the flexoelectric moduli f1111 and f1122 are comparable with their initial values and depend only on the initial value of f1212. The correction to f1212 is small, which allows one to use the perturbation theory. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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19. Lead indium niobate-lead magnesium niobate-lead titanate based whispering gallery mode resonator.
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Zhuang, Yongyong, Zhang, Yifan, Yang, Liu, Yu, Jianhui, Guo, Haisheng, Song, Kexin, Hu, Qingyuan, Yang, Lihong, Zhang, Hao, Wei, Xiaoyong, and Xu, Zhuo
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WHISPERING gallery modes , *RESONATORS , *INDIUM , *TITANATES , *PIEZOELECTRICITY , *MAGNESIUM , *LEAD titanate - Abstract
Whispering gallery mode resonators (WGMRs) have garnered significant interest due to their potential applications in the fields of electro-optic modulation and microwave to optical photon conversion. In this study, we have leveraged an electro-optic crystal, lead indium niobate-lead magnesium niobate-lead titanate (PIN-PMN-PT), to fabricate a high-quality WGMR. Our investigation revealed that the crystal composition used in this work is 0.24PIN-0.45PMN-0.31PT, and each element of the whole sample is homogeneously distributed. The dielectric properties of the sample revealed the necessity of limiting the temperature and external electric field frequency to below 100 °C and 106 Hz, respectively. The obtained optical quality factor value (Q value) of the resonator is ∼0.7 × 105. Impressively, our resonator could be conveniently tuned by exploiting the enormous inverse piezoelectric effect d31 of the crystal, thereby alleviating the need for precise fabrication. Furthermore, a theoretical analysis of our resonator revealed that a calculated resonance wavelength shift is within a broad range of 2.16 nm. Intriguingly, if the surface roughness of the resonator is reduced tenfold, we can increase the calculated Q value dependent on surface scattering by 104. Our finding showcases the tremendous potential of the PIN-PMN-PT crystal-based WGMR as versatile building blocks for a variety of applications in the burgeoning field of photonic technology. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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20. Comparing the performance fluctuation of direct and alternating current poling Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 ferroelectric single crystals.
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Hu, Yudong, Yang, Xiaoming, Zhang, Wenjie, Wang, Zujian, Tang, Haiyue, Su, Rongbing, Liu, Ying, Long, Xifa, and He, Chao
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FERROELECTRIC crystals , *ALTERNATING currents , *SINGLE crystals , *LEAD titanate , *DIELECTRIC loss , *PERMITTIVITY - Abstract
Large-size Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) based ferroelectric single crystals have been grown successfully by the vertical Bridgman method for application in the field of high-end piezoelectric devices. The piezoelectric and dielectric performance uniformity of PMN-PT based ferroelectric crystals is a critical application requirement. Recently, alternating current poling (ACP) has attracted much attention due to its low cost and high efficiency in improving the piezoelectric properties of PMN-PT based crystals. Here, we report the comparison of the performance fluctuation of direct current poling (DCP) and ACP Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) ferroelectric single crystals grown in the [110] direction using the vertical Bridgman method. The fluctuation of piezoelectric coefficient d33, dielectric constant ɛT33/ɛ0, and dielectric loss tanδ was presented. We found that the average d33 and ɛT33/ɛ0 of ACP samples are 1290 and 1500 pC/N and 3890 and 4290 for two different wafers, which were 18% and 23%, 21% and 26% higher than DCP samples. The tanδ of ACP samples was much lower than that of DCP samples. The DCP and ACP samples exhibited the close data of the fluctuation ratios of d33 and ɛT33/ɛ0. The fluctuation ratios of d33 and ɛT33/ɛ0 for DCP and ACP samples are all less than 10%. This work offers a reference for practical ACP technique applications. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
21. Electron beam-induced current imaging of ferroelectric domains and local polarization reversal in Hf0.5Zr0.5O2.
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Korostylev, Evgeny, Mikheev, Vitalii, Chernikova, Anna G., Zhuk, Maksim Yu., Chouprik, Anastasia, and Negrov, Dmitry V.
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PIEZORESPONSE force microscopy , *ELECTRON microscope techniques , *ELECTRIC currents , *SCANNING electron microscopes , *ELECTRONS , *LEAD titanate , *BARIUM titanate - Abstract
Because of their full compatibility with CMOS technology, HfO2-based ferroelectrics, and especially Hf0.5Zr0.5O2 (HZO), attract a lot of attention. However, the overwhelming majority of measurement techniques provides only information about the cumulative electrical response of many domains of HZO, i.e., at the macroscopic level. So far, only piezoresponse force microscopy technique was applied to visualize distinct ferroelectric domains in HZO and to analyze the local switching behavior in the microscopic level. This work introduces the possibility of using electron beam-induced current (EBIC) technique in the scanning electron microscope to visualize the gradual polarization reversal of HZO and to obtain the local polarization dynamics. We show that although the local EBIC signal is affected by surrounding domains, studying the variations in the ferroelectric response of individual domains as well as the spread of the local stiffness and local imprint is possible by this method. Besides, we show the connection between the EBIC current and an electric field across passive non-ferroelectric layers at interfaces between HZO and metal electrodes, which opens up additional opportunities to use the EBIC technique for investigations of interface-dependent properties of HZO ferroelectrics in the future. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
22. Electron beam-induced current imaging of ferroelectric domains and local polarization reversal in Hf0.5Zr0.5O2.
- Author
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Korostylev, Evgeny, Mikheev, Vitalii, Chernikova, Anna G., Zhuk, Maksim Yu., Chouprik, Anastasia, and Negrov, Dmitry V.
- Subjects
PIEZORESPONSE force microscopy ,ELECTRON microscope techniques ,ELECTRIC currents ,SCANNING electron microscopes ,ELECTRONS ,LEAD titanate ,BARIUM titanate - Abstract
Because of their full compatibility with CMOS technology, HfO
2 -based ferroelectrics, and especially Hf0.5 Zr0.5 O2 (HZO), attract a lot of attention. However, the overwhelming majority of measurement techniques provides only information about the cumulative electrical response of many domains of HZO, i.e., at the macroscopic level. So far, only piezoresponse force microscopy technique was applied to visualize distinct ferroelectric domains in HZO and to analyze the local switching behavior in the microscopic level. This work introduces the possibility of using electron beam-induced current (EBIC) technique in the scanning electron microscope to visualize the gradual polarization reversal of HZO and to obtain the local polarization dynamics. We show that although the local EBIC signal is affected by surrounding domains, studying the variations in the ferroelectric response of individual domains as well as the spread of the local stiffness and local imprint is possible by this method. Besides, we show the connection between the EBIC current and an electric field across passive non-ferroelectric layers at interfaces between HZO and metal electrodes, which opens up additional opportunities to use the EBIC technique for investigations of interface-dependent properties of HZO ferroelectrics in the future. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
23. Ferroelectric polarization and interface engineering coupling of Z-scheme ZnIn2S4/α-In2Se3 heterostructure for efficient photocatalytic water splitting.
- Author
-
Li, Jiayi, Lin, Yanming, Zhang, Minjie, Peng, Ying, Wei, Xinru, Wang, Zhengkun, Jiang, Zhenyi, and Du, Aijun
- Subjects
- *
HYDROGEN production , *ENERGY shortages , *MANUFACTURING processes , *ENGINEERING , *CHARGE transfer , *BARIUM titanate , *LEAD titanate , *HYDROGEN as fuel - Abstract
It is of great significance to design an efficient heterostructure for photocatalytic hydrogen production to solve the energy shortage and environmental crisis. In this letter, we investigate the structure, electron of interface, optical, charge transfer, and photocatalytic mechanism of three different ZnIn2S4/α-In2Se3 heterostructures by hybrid density functional calculation. It is interesting that the presence of an external electric field not only can change the bandgap but also can modulate the band alignment type. Among them, heterostructure A belongs to type II heterostructure, and heterostructure B and C belong to a Z-scheme heterostructure. Especially in heterostructure C, the electrons deposited on CBM of a ZnIn2S4 monolayer will play an important role in the hydrogen production process. Meanwhile, the small bandgap of ZnIn2S4/α-In2Se3 Z-scheme heterostructures enables it to obtain a wide light absorption range. Therefore, this study contributes to the design of a novel and potential Z-scheme heterostructure photocatalyst with broad application prospects in both electronic and optoelectronic fields. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
24. Controlling ferroelectric properties in Y-doped HfO2 thin films by precise introduction of oxygen vacancies.
- Author
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Dmitriyeva, Anna V., Zarubin, Sergei S., Konashuk, Aleksei S., Kasatikov, Sergey A., Popov, Victor V., and Zenkevich, Andrei V.
- Subjects
- *
PHOTOVOLTAIC effect , *THIN films , *X-ray absorption near edge structure , *NONVOLATILE memory , *COMPUTER storage devices , *PULSED laser deposition , *FERROELECTRIC capacitors , *LEAD titanate - Abstract
Thin-film ferroelectric doped hafnia has emerged as a promising candidate for non-volatile computer memory devices due to its CMOS compatibility. The ferroelectricity in thin-film HfO2 is defined by the polar orthorhombic phase, whose stabilization depends on various parameters, such as doping species, stress, thickness, crystallization annealing temperature, etc. The concentration of oxygen vacancies is yet another parameter affecting the stabilization of the ferroelectric phase in HfO2 thin films. Here, we report on the effect of oxygen vacancies introduced in Y-doped HfO2 (HYO) films during reactive pulsed laser deposition on their ferroelectric properties, which we systematically study by correlating structural and electrical properties. Among different techniques, near-edge x-ray absorption fine structure analysis is successfully employed to distinguish between structurally similar ferroelectric orthorhombic and paraelectric tetragonal phases. It is shown that oxygen vacancies introduced at a certain concentration in HYO films can be used as a tool to control the phase composition as well as to decrease the formation energy (crystallization temperature) of the ferroelectric phase. Based on these results, we demonstrate a back-end-of-line compatible ferroelectric HYO capacitor device with competitive functional properties. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
25. On the origin of polarization fatigue and Curie–von Schweidler relaxation current in Pb(Zrx,Ti1−x)O3 ferroelectric thin films: A unique mechanism based on charge trapping by interface defects.
- Author
-
Bouregba, Rachid
- Subjects
- *
FERROELECTRIC thin films , *DIELECTRIC relaxation , *FERROELECTRIC materials , *MATERIAL fatigue , *LEAD titanate , *X chromosome - Abstract
This article discusses the widespread problem of polarization fatigue in ferroelectric materials. After a review of the bibliographical data on this topic but also on the older and equally widespread problem of dielectric relaxation in solids, a possible correlation between these two phenomena is established by observing that the decrease with time of polarization obeys the Curie–von Schweidler (CVS) law like the relaxation current. An electrical model involving a charge trapping mechanism by electronic defects in bandgap at the contact/ferroelectric interface is then developed, which simultaneously explains polarization fatigue and relaxation current. The CVS law is found considering interface traps with a continuum of time constants. This study sheds new light on the origin of these phenomena, which remain unexplained to date. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
26. The influence of crystallographic texture on structural and electrical properties in ferroelectric Hf0.5Zr0.5O2.
- Author
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Lee, Younghwan, Broughton, Rachel A., Hsain, H. Alex, Song, Seung Keun, Edgington, Patrick G., Horgan, Madison D., Dowden, Amy, Bednar, Amanda, Lee, Dong Hyun, Parsons, Gregory N., Park, Min Hyuk, and Jones, Jacob L.
- Subjects
- *
CRYSTAL texture , *ELECTRICAL steel , *SURFACE energy , *THIN films , *LEAD titanate , *SEMICONDUCTOR industry , *COMMUNITIES - Abstract
Ferroelectric (Hf,Zr)O2 thin films have attracted increased interest from the ferroelectrics community and the semiconductor industry due to their ability to exhibit ferroelectricity at nanoscale dimensions. The properties and performance of the ferroelectric (Hf,Zr)O2 films generally depend on various factors such as surface energy (e.g., through grain size or thickness), defects (e.g., through dopants, oxygen vacancies, or impurities), electrodes, interface quality, and preferred crystallographic orientation (also known as crystallographic texture or simply texture) of grains and/or domains. Although some factors affecting properties and performance have been studied extensively, the effects of texture on the material properties are still not understood. Here, the influence of texture of the bottom electrode and Hf0.5Zr0.5O2 (HZO) films on properties and performance is reported. The uniqueness of this work is the use of a consistent deposition process known as Sequential, No-Atmosphere Processing (SNAP) that produces films with different preferred orientations yet minimal other differences. The results shown in this study provide both new insight on the importance of the bottom electrode texture and new fundamental processing-structure–property relationships for the HZO films. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
27. Unveiling the strain and structural ferroelectric phase transition induced by temperature in lead titanate perovskite modified with 40% of calcium.
- Author
-
Ribeiro Galão, Larissa, Garcia, Ducinei, and Estrada, Flávia Regina
- Subjects
- *
PHASE transitions , *TRANSITION temperature , *FERROELECTRIC transitions , *TITANATES , *LEAD titanate , *PERMITTIVITY , *RIETVELD refinement - Abstract
Structurally correlated ferroelectric phase transitions induced by temperature are reported for the solid solution Pb0.6Ca0.4TiO3 compound. Such phase transitions were analyzed by considering different parameters, such as lattice parameters, microstrain, dielectric properties, and thermal analysis. Synchrotron x-ray diffraction and Rietveld refinement studies revealed a tetragonal symmetry from room temperature up to ∼550 K and uniaxial microstrain from room temperature to ∼400 K. The first thermally driven phase transition observed was from displacive ferroelectric tetragonal symmetry to another non-displacive tetragonal symmetry. The next phase transition was from the tetragonal to cubic. The electric permittivity as a function of temperature for frequency from 1 kHz to 1 MHz and the differential scanning calorimetry report features typical of ferroelectric–paraelectric phase transition only around 400 K, and no other abrupt change in properties is observed at 550 K, indicating the sequence of first- and then second-order phase transition. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
28. The influence of crystallographic texture on structural and electrical properties in ferroelectric Hf0.5Zr0.5O2.
- Author
-
Lee, Younghwan, Broughton, Rachel A., Hsain, H. Alex, Song, Seung Keun, Edgington, Patrick G., Horgan, Madison D., Dowden, Amy, Bednar, Amanda, Lee, Dong Hyun, Parsons, Gregory N., Park, Min Hyuk, and Jones, Jacob L.
- Subjects
CRYSTAL texture ,ELECTRICAL steel ,SURFACE energy ,THIN films ,LEAD titanate ,SEMICONDUCTOR industry ,COMMUNITIES - Abstract
Ferroelectric (Hf,Zr)O
2 thin films have attracted increased interest from the ferroelectrics community and the semiconductor industry due to their ability to exhibit ferroelectricity at nanoscale dimensions. The properties and performance of the ferroelectric (Hf,Zr)O2 films generally depend on various factors such as surface energy (e.g., through grain size or thickness), defects (e.g., through dopants, oxygen vacancies, or impurities), electrodes, interface quality, and preferred crystallographic orientation (also known as crystallographic texture or simply texture) of grains and/or domains. Although some factors affecting properties and performance have been studied extensively, the effects of texture on the material properties are still not understood. Here, the influence of texture of the bottom electrode and Hf0.5 Zr0.5 O2 (HZO) films on properties and performance is reported. The uniqueness of this work is the use of a consistent deposition process known as Sequential, No-Atmosphere Processing (SNAP) that produces films with different preferred orientations yet minimal other differences. The results shown in this study provide both new insight on the importance of the bottom electrode texture and new fundamental processing-structure–property relationships for the HZO films. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
29. Effect of iron acceptor doping and calcium donor doping in potassium sodium niobate‐based lead‐free piezoceramics.
- Author
-
Azadeh, Maryam, Zhao, Changhao, Pawadi, Apoorva, Gao, Shuang, and Frömling, Till
- Subjects
- *
POTASSIUM niobate , *POINT defects , *DIELECTRIC loss , *CALCIUM , *IRON , *PIEZOELECTRIC ceramics , *POTASSIUM , *LEAD titanate - Abstract
Lead‐free potassium sodium niobate (KNN) ferroelectrics have emerged as promising alternatives to lead‐based materials due to their reduced toxicity and sometimes enhanced properties. The opportunity to modify the ferroelectric properties by doping, nevertheless, differs from lead‐based ceramics. A much lower impact with increasing dopant concentration was observed. This study systematically investigates the differences in defect chemistry of Na0.475K0.475Li0.065Nb0.92Ta0.08O3 ceramics through iron (Fe) acceptor doping and calcium (Ca) donor doping at varying concentrations. From the defect chemical point of view, it becomes evident that the impact of intrinsic defects on the electrical properties exceeds the effect of extrinsic defects induced by doping. The performance of the donor‐doped (Ca2+) ceramics closely resembles that of undoped KNN. Thus, hardly any change in ferroelectric properties and conductivity is observed. For the Fe‐doped samples, the conductivity and its contribution to the dielectric loss increased, which is not to the benefit of an application as a ferroelectric. Therefore, the concepts of "softening" and "hardening" of ferroelectric properties by doping are incompatible with regularly sintered KNN ceramics. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
30. Improved relaxor ferroelectrics and energy storage performance of polycrystalline Ba0.95Sr0.05Ti2O5 ceramics modified with La dopants.
- Author
-
Tian, Yongshang, Ma, Mingyang, Chen, Yuqian, Liu, Zhiwen, Ji, Xiang, Wu, Haitao, and Jing, Qiangshan
- Subjects
- *
ENERGY storage , *CERAMICS , *RELAXOR ferroelectrics , *ELECTRONIC ceramics , *POTENTIAL energy , *DIELECTRIC materials , *ARRHENIUS equation , *DOPING agents (Chemistry) , *LEAD titanate - Abstract
Lead-free relaxor ferroelectrics are useful in energy storage applications. In particular, BaTi 2 O 5 -based dielectric materials may have great potential for such applications. In this study, polycrystalline Ba 0.95 Sr 0.05 Ti 2 O 5 - x La (BST2- x La) ceramics were synthesized using a standard solid-state reaction method with as-prepared nanoparticles prepared via a modified Pechini polymeric precursor method. The structural and electrical properties of the BST2- x La ceramics were systematically investigated using a series of measurements. The phase analysis results confirm that La3+ is a donor dopant that replaced Ba2+ sites in the structure, which results in a decrease in oxygen vacancies to maintain charge neutrality. The intrinsic electronic conduction mechanism for electrical conductivity was evaluated from the fitted activation energy based on the Arrhenius equation. The relaxor ferroelectric behaviour and energy storage density and efficiency are improved by the addition of a small amount of lanthanum (<3.6 mol%) because of the charge and ionic radius mismatch in the structure. These results suggest that lanthanum can effectively optimise the relaxor ferroelectrics of BST2- x La ceramics, which have promising potential as energy storage materials. • Pure monoclinic-phase polycrystalline BST2- x La ceramics were synthesized. • La3+ acted as a donor dopant in the structure. • Mechanism of intrinsic electronic conduction in the ceramics was deduced. • La3+ could optimise the relaxor ferroelectric properties of BST2- x La ceramics. • The energy storage density and efficiency were improved at small values of x. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Enhanced energy storage and cycling stability of (Sr0.7La0.2)(Mg1/3Nb2/3)O3-modified K0.5Na0.5NbO3 ceramics via multiple synergistic strategies.
- Author
-
Duan, Xueliang, Wang, Juanjuan, Chai, Qizhen, Ma, Pengkang, Du, Hongliang, Jin, Li, Lai, Fusheng, Peng, Zhanhui, Chao, Xiaolian, and Lu, Jiangbo
- Subjects
- *
ENERGY storage , *CYCLING , *FERROELECTRIC ceramics , *ENERGY density , *CERAMICS , *LEAD titanate , *CERAMIC capacitors , *FERROELECTRIC polymers - Abstract
Ceramic capacitors are widely used devices due to their excellent characteristics, such as rapid charge and discharge rates and high power density. However, simultaneously attaining exceptional energy storage performance and outstanding cycling stability in ceramic-based energy storage capacitors remains a considerable challenge. In this work, a multi-scale synergistic optimization strategy was proposed to enhance the energy storage performance and cycling stability of K 0.5 Na 0.5 NbO 3 ceramics, accomplished through grain refinement, introducing polar nanoregions (PNRs), and inducing weakly polar pseudo-cubic phases. As a result, ultrafine grains (∼110 nm), excellent energy storage performance [energy storage density (W rec) ∼ 3.16 J/cm3, energy storage efficiency (η) ∼ 65%], and incredible cycling stability (W rec variation: ∼0.09%, η variation: ∼0.28%) are concurrently realized in the 0.93K 0.5 Na 0.5 NbO 3 -0.07(Sr 0.7 La 0.2)(Mg 1/3 Nb 2/3)O 3 relaxation ferroelectric ceramic. This work investigates the microscopic origins of the improved energy storage performance of KNN-based ceramics and presents a synergistic optimization strategy to achieve exceptional energy storage performance and incredible cycling stability. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
32. Origin of high‐temperature piezoelectric stability and polar nanoregions dynamics in 0.55Bi(Mg1/2Ti1/2)O3–0.45PbTiO3.
- Author
-
Chen, Kaiyuan, Yan, Tianxiang, Lei, Xiuyun, Lanceros‐Méndez, Senentxu, Yuan, Zhi, Fang, Liang, Peng, Biaolin, Wang, Dawei, Liu, Laijun, and Zhang, Qi
- Subjects
- *
PHASE transitions , *PIEZOELECTRIC ceramics , *LEAD titanate , *PHONONS - Abstract
The 0.55Bi(Mg1/2Ti1/2)O3–0.45PbTiO3 ceramics exhibit notable dielectric anomalies across three temperature ranges. The low‐temperature anomaly is attributed to a reentrant dipole glass‐like relaxor behavior; the mid‐temperature anomaly results from a ferro‐paraelectric phase transition; and the high‐temperature anomaly is associated with a diffuse phase transition. The system demonstrates favorable piezoelectric, electromechanical, and ferroelectric properties. Specifically, the ceramic presents a piezoelectric coefficient (d33) of 220 pC/N, an electromechanical coupling factor (kp) of 27%, and a remanant polarization (Pr) of 32.5 μC/cm2. Moreover, it maintains an operational capability up to 643 K. The unsaturated P(E) loops are formed through the coupling polarization between polar nanoregions (PNRs) and P4mm ferroelectric domains. By examining the electrical modulus, the dynamic PNRs resulting from ferroelectric phonon localization and the formation of P4mm ferroelectric domains were analyzed. The result reveals a mesoscale coupling relationship between the origin of high‐temperature piezoelectric stability and the dynamics of PNRs, thereby providing noble insights into the (1 − x)BiMeO3–xPbTiO3 system. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
33. Origin of high‐temperature piezoelectric stability and polar nanoregions dynamics in 0.55Bi(Mg1/2Ti1/2)O3–0.45PbTiO3.
- Author
-
Chen, Kaiyuan, Yan, Tianxiang, Lei, Xiuyun, Lanceros‐Méndez, Senentxu, Yuan, Zhi, Fang, Liang, Peng, Biaolin, Wang, Dawei, Liu, Laijun, and Zhang, Qi
- Subjects
PHASE transitions ,PIEZOELECTRIC ceramics ,LEAD titanate ,PHONONS - Abstract
The 0.55Bi(Mg1/2Ti1/2)O3–0.45PbTiO3 ceramics exhibit notable dielectric anomalies across three temperature ranges. The low‐temperature anomaly is attributed to a reentrant dipole glass‐like relaxor behavior; the mid‐temperature anomaly results from a ferro‐paraelectric phase transition; and the high‐temperature anomaly is associated with a diffuse phase transition. The system demonstrates favorable piezoelectric, electromechanical, and ferroelectric properties. Specifically, the ceramic presents a piezoelectric coefficient (d33) of 220 pC/N, an electromechanical coupling factor (kp) of 27%, and a remanant polarization (Pr) of 32.5 μC/cm2. Moreover, it maintains an operational capability up to 643 K. The unsaturated P(E) loops are formed through the coupling polarization between polar nanoregions (PNRs) and P4mm ferroelectric domains. By examining the electrical modulus, the dynamic PNRs resulting from ferroelectric phonon localization and the formation of P4mm ferroelectric domains were analyzed. The result reveals a mesoscale coupling relationship between the origin of high‐temperature piezoelectric stability and the dynamics of PNRs, thereby providing noble insights into the (1 − x)BiMeO3–xPbTiO3 system. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
34. Simulation and comparison of power generation through vibrational analysis for PMN-PZT on silicon substrate and PMN-PZT on aluminum based MEMS piezoelectric energy harvester.
- Author
-
Kumar, K. C. Dileep, Lakshmi, S. Vidhya, and Azariah, J. Cyril Robinson
- Subjects
- *
PIEZOELECTRIC materials , *ENERGY harvesting , *ALUMINUM , *ERROR rates , *SILICON , *LEAD titanate , *TITANATES - Abstract
This study employs a MEMS piezoelectric vibrational energy harvesting laboratory to simulate and compare the average harvested power and natural frequency for piezoelectric materials like lead magnesium niobate-lead zirconate titanate (PMN-PZT) on silicon and aluminium substrates of thicknesses ranging from 80 m to 800 m. Both instruments were put through an independent sample t-test using SPSS's statistical analysis options, with a pretest power of 80% and an error rate of =0.05. SPSS discovered that the average harvested power for the PMN-PZT/Si based MEMS energy harvester and the PMN-PZT/Al based MEMS energy harvester were both 3.31E-05 W and 3.38E-02 W, respectively, both of which were statistically insignificant at the p 0.05 level. The PMN-PZT/Al based MEMS piezoelectric energy harvester has a somewhat lower average collected power and natural frequency than PMN-PZT/Si, making it a viable alternative for low power applications. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. Coupling of ferroelectric and valley properties in 2D materials.
- Author
-
Zheng, Jun-Ding, Zhao, Yi-Feng, Tan, Yi-Fan, Guan, Zhao, Zhong, Ni, Yue, Fang-Yu, Xiang, Ping-Hua, and Duan, Chun-Gang
- Subjects
- *
LEAD titanate , *FERROELECTRICITY , *MAGNETIC fields , *FERROELECTRIC crystals , *HETEROSTRUCTURES - Abstract
Two-dimensional (2D) valleytronic materials are both fundamentally intriguing and practically appealing to explore novel physics and design next-generation devices. However, traditional control means such as optic pumping or magnetic field cannot meet the demands of modern electron devices for miniaturization, low-dissipation, and non-volatility. Thus, it is attractive to combine the ferroelectric property with valley property in a single compound. In this paper, the recent progress of ferroelectric-valley coupling is reviewed. First, we briefly recall the development of valleytronics in the past several years. Then, various structures demonstrating ferroelectric-valley coupling, including heterostructures and intrinsic materials, are introduced. Subsequently, we describe ferroelectric-valley coupling in sliding and adsorption system and the unconventional ferroelectricity in the moiré system. Finally, we discuss the research status and outlook. We hope that this perspective will be helpful to bridge the gap between valleytronics and ferroelectrics in 2D materials and inspire further exciting findings. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
36. New strategy for simultaneously achieving enhanced piezoelectricity and deferred Td in Bi0.5Na0.5TiO3-based relaxor ferroelectrics.
- Author
-
Yang, Diyan, Wu, Xiaojun, Wang, Xianya, Xue, Haoyue, Yin, Jie, and Wu, Jiagang
- Subjects
- *
PIEZOELECTRICITY , *LEAD titanate , *RELAXOR ferroelectrics , *ELECTRIC fields , *FERROELECTRICITY - Abstract
The inverse relationship between the piezoelectricity and depolarization temperature Td impedes the development of Bi0.5Na0.5TiO3 (BNT)-based ceramics. To realize the goal of enhancing the piezoelectricity together with a deferred Td, the intrinsic formation mechanism of Td should be well understood. In this work, considering the role A-site cations play in manipulating the relaxor behavior of BNT, Pb2+, Ba2+, Sr2+, and Ca2+ (with distinguished ferroelectricity and polarity) are selected to investigate the formation mechanism of Td. Td reflects the stability of polarizations, which could be manipulated through modifying the polarization field and local electric and strain fields. The introduction of Pb2+ and Ba2+ increases the long-range correlated ferroelectric P4mm phase, which strengthens the polarization field and stabilizes polarizations, while the introduction of Sr2+ and Ca2+ increases the short-range correlated ferroelectric P4bm phase and the non-ferroelectric phase, which weakens the polarization field and destabilizes polarizations. Domain structures captured by a piezoresponse force microscope corroborate the effect of Pb2+ and Ba2+ in stabilizing polarizations and Sr2+ and Ca2+ in destabilizing polarizations. Therefore, by introducing the ferroelectric component that exhibits a different local symmetry to the BNT-matrix and can also provide a strong polarization field, the simultaneously enhanced piezoelectricity together with a deferred Td could be realized, as validated in the designed BNT-xPbTiO3 system. This work investigates the formation mechanism of Td and guides the design of high-performance systems in BNT-based materials, benefiting the understanding of BNT-based relaxor ferroelectrics. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
37. Effects of thin metal contacts on few-layer van der Waals ferrielectric CuInP2S6.
- Author
-
O'Hara, Andrew, Tao, Lei, Neumayer, Sabine M., Maksymovych, Petro, Balke, Nina, and Pantelides, Sokrates T.
- Subjects
- *
FERROELECTRIC materials , *FLEXIBLE electronics , *LEAD titanate , *METALS , *FERROELECTRICITY , *FERROELECTRIC crystals - Abstract
Out-of-plane polarized ferroelectric materials in a capacitive structure provide a key component for several technological applications. Furthermore, two-dimensional materials are expected to aid in the quest for both ultrathin and flexible electronics. Of the various two-dimensional ferroelectrics with out-of-plane polarization, CuInP2S6 is special in that the Cu atoms are highly mobile and it has been shown to possess both low- and high-polarization states. Using density-functional-theory calculations, we explore the stabilization of the ferroelectric state for several prototypical metal contacts (Gr, Ni, Cu, Au, and Ag). In all cases, we find that the ferroelectric state can be stabilized at fewer layers than in the freestanding case. For all of the considered conventional metal contacts, we also find the existence of a quasi-ferroelectric state that stabilizes a polar phase for thicknesses greater than two layers of CIPS. In the cases of Au and Ag, interfacial alignment and strain can be used to stabilize ferroelectricity at the bilayer limit. Furthermore, we find that the strength of the interaction between the contact and CuInP2S6 also leads to stabilization of the high-polarization state when ferroelectricity is stabilized. Lastly, energy-barrier calculations show that the system is still switchable in the presence of contact doping from the metal contacts. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
38. Effects of thin metal contacts on few-layer van der Waals ferrielectric CuInP2S6.
- Author
-
O'Hara, Andrew, Tao, Lei, Neumayer, Sabine M., Maksymovych, Petro, Balke, Nina, and Pantelides, Sokrates T.
- Subjects
FERROELECTRIC materials ,FLEXIBLE electronics ,LEAD titanate ,METALS ,FERROELECTRICITY ,FERROELECTRIC crystals - Abstract
Out-of-plane polarized ferroelectric materials in a capacitive structure provide a key component for several technological applications. Furthermore, two-dimensional materials are expected to aid in the quest for both ultrathin and flexible electronics. Of the various two-dimensional ferroelectrics with out-of-plane polarization, CuInP
2 S6 is special in that the Cu atoms are highly mobile and it has been shown to possess both low- and high-polarization states. Using density-functional-theory calculations, we explore the stabilization of the ferroelectric state for several prototypical metal contacts (Gr, Ni, Cu, Au, and Ag). In all cases, we find that the ferroelectric state can be stabilized at fewer layers than in the freestanding case. For all of the considered conventional metal contacts, we also find the existence of a quasi-ferroelectric state that stabilizes a polar phase for thicknesses greater than two layers of CIPS. In the cases of Au and Ag, interfacial alignment and strain can be used to stabilize ferroelectricity at the bilayer limit. Furthermore, we find that the strength of the interaction between the contact and CuInP2 S6 also leads to stabilization of the high-polarization state when ferroelectricity is stabilized. Lastly, energy-barrier calculations show that the system is still switchable in the presence of contact doping from the metal contacts. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
39. Narrow bandgap potassium titanate-molybdate-based d0 ferroelectrics.
- Author
-
Shafir, Or and Grinberg, Ilya
- Subjects
- *
FERROELECTRIC crystals , *FERROELECTRIC materials , *FERROELECTRICITY , *PHOTOVOLTAIC effect , *FERROELECTRIC polymers , *TITANATES , *LEAD titanate , *SOLID solutions - Abstract
The bulk photovoltaic effect observed in ferroelectric materials can enable photovoltaic performance beyond the Shockley–Queisser limit of efficiency. This requires the use of ferroelectrics with strong polarization and low bandgap (Eg) that are typically contradictory in the common perovskite oxides ferroelectrics. Here, we use first-principles calculations to study the KNbO3–K(Ti0.5Mo0.5)O3 (KNTM) solid solutions as possible narrow-gap ferroelectric materials. KTM, the end-member of the recently discovered KNTM solid solution system, maintains a ferroelectric polarization similar to that of other K-based systems due to its d0 configuration at the B-site. The substitution of Nb in KTM reduces Eg from 2.9 of KTM to 1.83 eV for an unstrained system and 1.7 eV for a compressively strained system, while maintaining ferroelectricity. The combination of narrow Eg, strong ferroelectricity, low toxicity, and abundance of the constituent elements make Nb-substituted KTM a promising candidate material for photoferroelectric applications. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
40. Piezoelectric acoustic wave characteristics of Pb(In0.5Nb0.5)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 single crystal substrate: A comparative study with and without SiO2 overlay.
- Author
-
Zhang, Qiaozhen, Du, Rufan, Li, Baichuan, Liu, Huiling, Zhao, Xiangyong, Chen, Ziyun, and Luo, Haosu
- Subjects
- *
SOUND waves , *ACOUSTIC surface waves , *SINGLE crystals , *QUALITY factor , *TRANSDUCERS , *FERROELECTRIC crystals , *ELECTROMECHANICAL effects , *LEAD titanate - Abstract
This paper investigates the excitation and propagation characteristics of a piezoelectric acoustic wave propagating in a rotated Y-cut X-propagating Pb(In0.5Nb0.5)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) relaxor-based ferroelectric single crystal substrate. Numerical simulations were performed to evaluate the acoustic wave properties by FEM software COMSOL. For comparison, two types of structures are taken into consideration: one is the traditional metal electrode/YX-PIN-PMN-PT and the other is silicon dioxide (SiO2) overlay/metal electrode/YX-PIN-PMN-PT substrate. It is shown that shear-horizontal (SH)-type piezoelectric boundary acoustic waves (PBAW) exist in the SiO2 overlay/metal electrode/YX-PIN-PMN-PT substrate and offer a fairly large electromechanical coupling factor K2 of 30%. Compared to a surface acoustic wave excited in the metal electrode/YX-PIN-PMN-PT substrate, enlarged phase velocity and significantly improved quality factor (∼3500) are simultaneously obtained for SH-type PBAW, which are promising for electromechanical transducer applications with high performance. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
41. Structure and relaxor ferroelectric behavior of the novel tungsten bronze type ceramic Sr5BiTi3Nb7O30.
- Author
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He, Qiuwei, Schmid, Siegbert, Chen, Xue, Peng, Biaolin, Li, ChunChun, Hu, Changzheng, Liu, Laijun, and Hinterstein, Manuel
- Subjects
- *
TUNGSTEN bronze , *LEAD titanate , *RELAXOR ferroelectrics , *DIPOLE moments , *FERROELECTRIC transitions , *CERAMICS , *FERROELECTRIC materials - Abstract
This paper reports a novel lead-free tungsten bronze type ceramic, Sr5BiTi3Nb7O30, prepared by a conventional high-temperature solid-state reaction route. The crystal structure identified using synchrotron x-ray diffraction data and Raman spectroscopy for Sr5BiTi3Nb7O30 could be described as an average structure with the centrosymmetric space group P4/mbm and a local non-centrosymmetric structure at room temperature. In the second-harmonic generation measurement, the Sr5BiTi3Nb7O30 compound exhibits second-order nonlinear optical behavior, which suggests the material is ferroelectric. Temperature dependence of the dielectric permittivity indicates that the dielectric anomaly in Sr5BiTi3Nb7O30, associated with the disorder on the A and B sites, results in strong frequency dispersion with a low phase-transition temperature. A macroscopic and phenomenological statistical model was employed to describe the temperature dependence of the dielectric responses of Sr5BiTi3Nb7O30 and Sr6Ti2Nb8O30. The calculated sizes of polar nanoregions for both compounds imply structural disorder induced by A and B sites, giving rise to a more diffuse ferroelectric transition for Sr5BiTi3Nb7O30. The smaller polar nanoregions with smaller electrical dipole moments can be activated at lower temperatures, leading to Sr5BiTi3Nb7O30 having a lower Tm (∼260 K) than other tungsten bronze type ferroelectrics. This work charts a promising feasible route to the development of improved relaxor ferroelectrics in tungsten bronze type oxides. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
42. Structure and relaxor ferroelectric behavior of the novel tungsten bronze type ceramic Sr5BiTi3Nb7O30.
- Author
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He, Qiuwei, Schmid, Siegbert, Chen, Xue, Peng, Biaolin, Li, ChunChun, Hu, Changzheng, Liu, Laijun, and Hinterstein, Manuel
- Subjects
TUNGSTEN bronze ,LEAD titanate ,RELAXOR ferroelectrics ,DIPOLE moments ,FERROELECTRIC transitions ,CERAMICS ,FERROELECTRIC materials - Abstract
This paper reports a novel lead-free tungsten bronze type ceramic, Sr
5 BiTi3 Nb7 O30 , prepared by a conventional high-temperature solid-state reaction route. The crystal structure identified using synchrotron x-ray diffraction data and Raman spectroscopy for Sr5 BiTi3 Nb7 O30 could be described as an average structure with the centrosymmetric space group P4/mbm and a local non-centrosymmetric structure at room temperature. In the second-harmonic generation measurement, the Sr5 BiTi3 Nb7 O30 compound exhibits second-order nonlinear optical behavior, which suggests the material is ferroelectric. Temperature dependence of the dielectric permittivity indicates that the dielectric anomaly in Sr5 BiTi3 Nb7 O30 , associated with the disorder on the A and B sites, results in strong frequency dispersion with a low phase-transition temperature. A macroscopic and phenomenological statistical model was employed to describe the temperature dependence of the dielectric responses of Sr5 BiTi3 Nb7 O30 and Sr6 Ti2 Nb8 O30 . The calculated sizes of polar nanoregions for both compounds imply structural disorder induced by A and B sites, giving rise to a more diffuse ferroelectric transition for Sr5 BiTi3 Nb7 O30 . The smaller polar nanoregions with smaller electrical dipole moments can be activated at lower temperatures, leading to Sr5 BiTi3 Nb7 O30 having a lower Tm (∼260 K) than other tungsten bronze type ferroelectrics. This work charts a promising feasible route to the development of improved relaxor ferroelectrics in tungsten bronze type oxides. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
43. Amplification of pyroelectric device with WSe2 field effect transistor and ferroelectric gating.
- Author
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Mbisike, Stephen C., Eckart, Lutz, Phair, John W., Lomax, Peter, and Cheung, Rebecca
- Subjects
- *
FIELD-effect transistors , *FIELD-effect devices , *FERROELECTRICITY , *LEAD zirconate titanate , *PLATINUM electrodes , *LEAD titanate , *PLATINUM , *METAL oxide semiconductor field-effect transistors - Abstract
A WSe2 field effect transistor integrated with a lead zirconium titanate (PZT) pyroelectric device has been designed, fabricated, and tested and is described as the integrated pyroelectric device. The integrated device has been compared to a standalone pyroelectric device, which consists of PZT sandwiched between platinum electrodes. A pyroelectric coefficient of 1.755 × 10−4 C/m2K has been realized for our thin-film PZT (650 nm). The integrated device amplifies the output of the standalone device by over ten orders of magnitude as the current density calculated for the devices is 16 nA/mm2 and 1 nA/mm2, respectively. The interplay between the pyro- and ferro-induced polarization of the integrated device has been studied. From our observations, the ferroelectric gating controls directly the drain-source current output of the integrated device, showing anti-clockwise hysteresis behavior. The device shows promise for application in infrared sensing. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
44. Local ±[001]c off-centering nanoregions in silver niobate.
- Author
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Li, Gen, Liu, Hai, Zhao, Lei, Gao, Jing, Li, Jing-Feng, and Zhu, Jing
- Subjects
- *
ANTIFERROELECTRIC materials , *SILVER , *ENERGY storage , *LEAD titanate , *FERROELECTRICITY , *FERROELECTRIC crystals , *BARIUM titanate - Abstract
As a typical lead-free antiferroelectric material, silver niobate has attracted much attention in recent years due to its excellent performance in energy storage. In this work, based on a spherical aberration–corrected STEM-high angle annular dark field technique, the sites of each cation column of pure silver niobate and Ta-doped silver niobate were quantitatively obtained. Besides conventional antiferroelectric displacements along the ±[1−10]c directions, B-site ions were found to also deviate along ±[001]c directions and form many local off-centering nanoregions, which may induce weak ferroelectricity, just like polar nanoregions in relaxed ferroelectrics. Such results will further increase our understanding of silver niobate in the microscopic view and may help explain some unsolved questions. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
45. Full matrix electromechanical properties of textured Pb(In1/2Nb1/2)O3-Pb(Sc1/2Nb1/2)O3-PbTiO3 ceramic.
- Author
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Yang, Shuai, Qiao, Liao, Wang, Jing, Wang, Mingwen, Gao, Xiangyu, Wu, Jie, Li, Jinglei, Xu, Zhuo, and Li, Fei
- Subjects
- *
PIEZOELECTRIC devices , *PERMITTIVITY , *CERAMICS , *PIEZOELECTRIC ceramics , *FERROELECTRIC ceramics , *THERMAL stability , *LEAD titanate - Abstract
Textured relaxor-PbTiO3 (PT) ceramics possess advantages of crystal-like properties, high composition homogeneity, and low cost, and have, thus, received considerable attention from the piezoelectric community. To promote the applications of textured relaxor-PT ceramics, here we characterize the full electromechanical parameters (elastic, dielectric, and piezoelectric coefficients) and the frequency dependence of the coercive field (EC) for the recently reported textured Pb(In1/2Nb1/2)O3-Pb(Sc1/2Nb1/2)O3-PbTiO3 (PIN-PSN-PT) ceramic. Our results show that the textured PIN-PSN-PT ceramic possesses high piezoelectric coefficients (d31 = −365 pC N−1, d33 = 770 pC N−1, and g33 = 40.4 × 10−3 m2 C−1) and electromechanical coupling factors (k33 = 87% and kp = 82%), far outperforming those of the commercial ceramic PZT-5H (d31 = −274 pC N−1, d33 = 593 pC N−1, g33 = 1.97 × 10−2 m2 C−1, k33 = 75%, and kp = 65%). In addition, the textured PIN-PSN-PT ceramic exhibits lower dielectric constants (ɛ33S = 478) compared with PZT-5H and relaxor-PT crystals, which can greatly promote the sensitivity of receiving transducers. Moreover, the textured PIN-PSN-PT ceramic with a high Tr−t (172 °C) shows better thermal stability compared to commercial relaxor-PT crystals (Tr−t < 130 °C). The results presented here will benefit the development of piezoelectric devices made of textured ceramics. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
46. Significantly enhanced energy storage density and efficiency in flexible Bi3.15Nd0.85Ti3O12 thin film via periodic dielectric layers.
- Author
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Chen, Qianxin, Zhang, Yuan, Tang, Mingkai, Yang, Lei, Zhong, Xiangli, Ren, Chuanlai, and Zhong, Gaokuo
- Subjects
- *
ENERGY storage , *ENERGY density , *PULSED laser deposition , *THIN films , *LEAD titanate , *FERROELECTRIC capacitors , *BARIUM titanate , *NUTRIENT density - Abstract
Flexible energy storage based on ferroelectric capacitors enjoys high power density and rapid respond time, but the polarization fatigue problems limit its long-term reliability. Bi3.15Nd0.85Ti3O12 (BNT) is a lead-free ferroelectric material with fatigue-free properties, which is promising for applications in long-term ferroelectric devices. Nevertheless, the applications of BNT thin films for energy storage are restricted by their poor energy efficiency and low energy density. In this work, flexible BNT thin films with different numbers of SrTiO3 (STO) insert layers are fabricated on flexible mica substrates by an exquisitely designed dual-target pulsed laser deposition process, and the energy storage performances are effectively optimized via interface engineering. By inserting periodic STO dielectric layers with repetition periods of 100, the energy storage density (Wrec) and efficiency (η) are improved to ∼24.26 J cm−3 and ∼71.93%, which are, respectively, increased to 287% and 132% compared with the pure phase BNT thin film. Importantly, the improved Wrec and η can be well maintained under large bending deformation (bending radius as small as r = 4 mm) and within a wide temperature range (25–175 °C), suggesting its good stability and reliability. These results show that the involvement of periodic dielectric layers in BNT thin films can significantly enhance energy storage density and efficiency and effectively promote its applications in future flexible energy storage devices. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
47. Disruption of polar order in lead zirconate titanate by composition-modulated artificial superlattice.
- Author
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Sato, Yukio, Kimura, Goki, Kweon, Sang Hyo, Tan, Goon, and Kanno, Isaku
- Subjects
- *
LEAD titanate , *SCANNING transmission electron microscopy , *LEAD zirconate titanate , *UNIT cell , *CELL morphology - Abstract
Lead zirconate titanate (Pb (Zrx, Ti1−x)O3: PZT) is a well-known ferroelectric compound, in which long-range polar order is usually developed. In the present study, it was clarified by distortion-corrected atomic-scale scanning transmission electron microscopy imaging that long-range polar order is disrupted in PZT by utilizing composition-modulated superlattice. Shape of unit cell was unusual both in the Pb(Zr0.65Ti0.35)O3 (PZT65) and Pb(Zr0.30Ti0.70)O3 (PZT30) layers, which was due to mutual in-plane lattice constraint. By taking account of this, first-principles calculations clarified that multiple directions can be energetically favorable for lead-ion displacement, which explains a reason why long-range polar order was disrupted. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
48. Fe-enriched two-phase multiferroic composites based on lead ferroniobate - titanate and modified nickel ferrite.
- Author
-
Lisnevskaya, Inna V., Aleksandrova, Inga A., Reshetnikova, Elena A., Davydova, Alisa A., Sheptun, Ivan G., Raevski, Igor P., and Rusalev, Yury V.
- Subjects
- *
NICKEL ferrite , *TITANATES , *MAGNETIC traps , *PIEZOELECTRIC composites , *LEAD titanate , *COPPER , *CRYSTAL grain boundaries , *MAGNETIC properties - Abstract
Iron-enriched ferroelectrics are of particular interest as piezoactive components of piezoelectric-ferrite ME ceramics. This is due to the phase composition similarity and the reduction of expected interfacial doping effects during high-temperature calcination. This idea seems attractive, but laborious due to the significantly limited number of possible piezoelectric–ferrite combinations. Therefore, there is practically no data on such systems in the literature. ME composite ceramics based on the highly efficient Fe-containing Pb(Fe 0.5 Nb 0.5) 0.935 Ti 0.065 O 3 (PFNPT) ferroelectric has been studied. (100-х) wt.% Pb(Fe 0.5 Nb 0.5) 0.935 Ti 0.065 O 3 (PFNPT) + х wt.% Ni 0.9 Co 0.1 Cu 0.1 Fe 1.9 O 4-d (NCCF) composite systems has been obtained by the solid-state method at 1050 °C, with no foreign phases. The specimens densities amounted to ∼80% of the theoretical. It has been shown that the ME conversion efficiency and other composites properties are significantly influenced by the PFNPT precursor pre-treatment method. The maximum value of the ME coefficient ΔΕ/ΔΗ = 75 mV/(cm Oe) has been observed for specimens with x = 50–60 made from PFNPT powder with the addition of Li 2 CO 3. An increase in the ME composites sintering temperature to 1150 °C leads to the formation of Pb 2 Nb 2 O 7 foreign phase with a pyrochlore structure along the grain boundaries. The ME coefficient ΔΕ/ΔΗ does not exceed 15 mV/(cm⋅Oe). There is an threefold decrease in the composites piezoelectric parameters (piezoelectric coefficients d ij , g ij), as well as in their magnetic properties (magnetizations M S , M R) due to piezophase degradation, which is presumably associated with a change in the cations distribution over A and B sublattices of the spinel structure. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
49. Giant polarization in tetragonal-like BiFeO3 film via (Ba,Ca)TiO3 doping.
- Author
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Li, Teng, Zhu, Beibei, Zhuo, Hao, Hu, Shudong, Liu, Yiwen, Shao, Botao, Wang, Ke, Song, Dongsheng, Xu, Liqiang, and Chen, Feng
- Subjects
- *
SCANNING transmission electron microscopy , *LEAD titanate , *MULTIFERROIC materials , *TANTALUM , *METHODS engineering , *FERROELECTRICITY - Abstract
BiFeO3 is a multiferroic material, its tetragonality (T) phase usually exhibits large tetragonality (c/a ratio) and strong ferroelectricity. Unlike the commonly used method of strain engineering via substrate, here we present a general and practical approach for obtaining T-like phase BiFeO3 films through (Ba,Ca)TiO3 doping (BF-BCT). The BF-BCT film coherently grows on the La0.7Sr0.3MnO3/(La0.18Sr0.82)(Al0.59Ta0.41)O3 (001) substrate even at 180 nm thick, implying a very large critical thickness, and shows a large tetragonality of 1.12. Impressively, the films exhibit a giant remanent polarization (2Pr) of 320 μC/cm2, which is higher than the corresponding values of any other lead-free ferroelectric films reported to date. Cross-sectional scanning transmission electron microscopy measurements confirm the presence of the T-like phase in BF-BCT films, where the giant polarization might be attributed to the off-center B-site atom. The BF-BCT films are structurally homogeneous without any precipitation of the second phase. The giant polarization observed in the BF-BCT films indicate their great potential for application in next-generation storage and information devices. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. Superior energy storage density and bright upconversion emission in Er-modified KNN-based multifunctional ferroelectric ceramics.
- Author
-
Huan, Yu, Li, Changxiao, Wu, Lingzhi, Li, Peng, and Wei, Tao
- Subjects
- *
ENERGY storage , *ENERGY density , *PHOTON upconversion , *FERROELECTRIC ceramics , *ELECTRONIC equipment , *RARE earth oxides , *ERBIUM , *LEAD titanate - Abstract
Developing highly tunable multifunctional performances in one ferroelectric system is in line with the integration trend of electronic equipment. Herein, rare earth erbium (Er) modulated 0.95K 0.5 Na 0.5 NbO 3 –0.05Bi(Li 0.5 Nb 0. 5)O 3 – x %Er photoluminescent–ferroelectric energy storage multifunctional ceramics are prepared. All the compositions exhibit a similar grain size and compact microstructure. In addition, the optimized Er dopant enhances the enhanced relaxor characteristic and reduces oxygen vacancies. The introduction of Er3+ into perovskite lattice contributes to the observed photoluminescence behavior. Therefore, high effective energy storage density (W rec) of 7.17 J/cm3, energy storage efficiency (η) of 65.4%, and strong green/red upconversion photoluminescence are obtained in x = 0.2 sample. This work opens up a paradigm to develop multifunctional ferroelectric ceramics for application in electro-optical devices. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
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