Multiferroics, having both magnetic and electric orders withina single material, have been extensively studied for academiccuriosity and possible applications, including energy-efficientmemory and logic devices [1–3]...Multiferroics, having both magnetic and electric orders withina single material, have been extensively studied for academiccuriosity and possible applications, including energy-efficientmemory and logic devices [1–3]. Although several multiferroicmaterials have been reported for bulk single crystals, recentinterest has shifted towards atomically thin magnetic materials.Achieving multiferroic at the limit of few or single atomic layershas become a significant challenging [4,5].展开更多
Due to the atomic-level centrosymmetric spontaneous polarization,antiferroelectric materials exhibit a sensitively nonlinear capacitive response to plural physic fields(mainly electric field and temperature)in a certa...Due to the atomic-level centrosymmetric spontaneous polarization,antiferroelectric materials exhibit a sensitively nonlinear capacitive response to plural physic fields(mainly electric field and temperature)in a certain range,consequently leading to some superb material properties,e.g.,ripple suppression,elec-trocaloric cooling,and dielectric energy storage.However,there are many cognitive blanks about how this exotic multi-field relationε(E_(DC),T)is influenced and manipulated via microscopic structures in the anti-ferroelectrics.In this work,the classic antiferroelectric ceramics PLZT were selected to see this intelligent effect,based on a quad-parameterizedε(E_(DC))relation on the dependence of T.εrelations were studied under different material compositions,temperature,frequency,AC electric field,and DC electric field,re-vealing lattice/domain structure evolution and the underlying mechanism.The inherent phase stability,introduced random field,and hierarchical hysteresis states were found to co-dominate this multi-field nonlinear relation.This work would not only contribute to future progress in the current applications(ripple suppression/electrocaloric cooling/dielectric energy storage)but imply the possibility of co-sensing temperature and electric potential simply and smartly.展开更多
Reduced and internally biased oxide wafer (RAINBOW) Pb (Sn, Zr, Ti) O3 (PSZT) antiferroelectric ceramics are fabricated by chemical reduction. It is a kind of large displacement actuating materials composed of reduced...Reduced and internally biased oxide wafer (RAINBOW) Pb (Sn, Zr, Ti) O3 (PSZT) antiferroelectric ceramics are fabricated by chemical reduction. It is a kind of large displacement actuating materials composed of reduced and unreduced layers. It is found that PSZT is easily reduced and the optimal conditions for producing RAINBOW samples are determined to be 870°C for 2 to 3 h, which results in a reduced layer composed of metallic lead and refractory oxides (PbO, ZrO2 and ZrTiO4). The phase transitions from antiferroelectric state to ferroelectric state occur at lower field strength in RAINBOW samples compared with normal PSZT ceramics. Larger axial displacement is also obtained from RAINBOW samples by application of electric fields exceeding the phase switching level. However, the actuating properties of RAINBOW samples are dependent on the manner of applying load on it.展开更多
The phase transitions, dielectric properties, and polarization versus electric field （P-E） hysteresis loops of Pbo.97Lao.02（Zr0.42Sn0.58-xTix）O3 （0.13≤ x ≤0.18） （PLZST） bulk ceramics were systematically inve...The phase transitions, dielectric properties, and polarization versus electric field （P-E） hysteresis loops of Pbo.97Lao.02（Zr0.42Sn0.58-xTix）O3 （0.13≤ x ≤0.18） （PLZST） bulk ceramics were systematically investigated. This study exhibited a sequence of phase transitions by analyzing the change of the P-E hysteresis loops with increasing temperature. The anfiferroelectric （AFE） to ferroelectric （FE） phase boundary of PLZST with the Zr content of 0.42 was found to locate at the Ti content between 0.14 and 0.15. This work is aimed to improve the ternary phase diagram of lanthanum-doped PZST with the Zr content of 0.42 and will be a good reference for seeking high energy storage density in the PLZST system with low-Zr content.展开更多
The crystal and electronic structure of antiferroelectric squaric acid is studied using density functional theory method, and the exchange correlation effects are treated by the generalized approximation. In order to ...The crystal and electronic structure of antiferroelectric squaric acid is studied using density functional theory method, and the exchange correlation effects are treated by the generalized approximation. In order to understand the ferroelectricity of H2SQ in the molecular plane and the antiferroelectricity in whole crystal, the density of states, charge density distribution and band structure are calculated. The result showed that O2p and C2p play important roles in the interactions between layers. The hybridizations of 02s-Hls and 02p-Hls are responsible for the tendency to ferroelectricity within each layer.展开更多
The complex dielectric constant of pure and cerium doped calcium-barium-niobate (CBN) was studied at frequencies 20 Hz ≤ f ≤ 1 MHz in the temperature range 300 K ≤ T ≤ 650 K and compared with the results for the w...The complex dielectric constant of pure and cerium doped calcium-barium-niobate (CBN) was studied at frequencies 20 Hz ≤ f ≤ 1 MHz in the temperature range 300 K ≤ T ≤ 650 K and compared with the results for the well known ferroelectric relaxor strontium-barium-niobate (SBN). By the analysis of the systematically taken temperature and frequency dependent measurements of the dielectric constant the phase transition characteristic of the investigated materials was evaluated. From the results it must be assumed that CBN shows a slightly diffuse phase transition without relaxor behavior. Doping with cerium yields a definitely different phase transition characteristic with some indications for a relaxor type ferroelectric material, which are common from SBN.展开更多
Antiferroelectric materials are promising candidates for energy-storage applications due to their double hysteresis loops,which can deliver high power density.Among the antiferroelectric materials,AgNbO_(3)is proved a...Antiferroelectric materials are promising candidates for energy-storage applications due to their double hysteresis loops,which can deliver high power density.Among the antiferroelectric materials,AgNbO_(3)is proved attractive due to its environmental-friendliness and high potential for achieving excellent energy storage performance.However,the recoverable energy storage density of AgNbO_(3)ceramics is limited by their relatively low breakdown strength.Herein,the breakdown strength of the pure AgNbO_(3)ceramics prepared using the tape casting method is enhanced to 307 kV·cm^(-1),which is,to the best of our knowledge,among the highest values reported for pure AgNbO-3bulk ceramics.The high breakdown strength may be due to its dense microstructure and good crystallinity obtained by the tape casting method and the optimized sintering temperature.Owing to its enhanced breakdown strength,AgNbO_(3)ceramics show high recoverable energy storage density of 2.8 J·cm^(-3).These results have led to the development of lead-free antiferroelectric materials and devices with high energy storage density.展开更多
Antiferroelectric ferroelectric （AFE-FE） phase transition in ceramic Pbo.97Lao.02（Zro.75Snon36Tion14）O3 （PLZST） was studied by dielectric spectroscopy as functions of frequency （102-105 Hz） and pressure （0-50...Antiferroelectric ferroelectric （AFE-FE） phase transition in ceramic Pbo.97Lao.02（Zro.75Snon36Tion14）O3 （PLZST） was studied by dielectric spectroscopy as functions of frequency （102-105 Hz） and pressure （0-500 MPa） under a DC electric field. The hydrostatic pressure-dependent remnant polarization and dielectric constant were mea- sured. The results show that remnant polarization of the metastable rhombohedral ferroelectric PLZST poled ceramic decreases sharply and depoles completely at phase transition under hydrostatic pressure. The dielectric constant um dergoes an abrupt jump twice during a load and unload cycle under an electric field. The two abrupt jumps correspond to two phase transitions, FE AFE and AFE-FE.展开更多
Free-standing antiferroelectric Pb（Zr0.95Ti0.05O3（PZT（95/5）） thin film is fabricated on 200-nm-thick Pt foil by using pulsed laser deposition.X-ray diffraction patterns indicate that free-standing PZT（95/5） fil...Free-standing antiferroelectric Pb（Zr0.95Ti0.05O3（PZT（95/5）） thin film is fabricated on 200-nm-thick Pt foil by using pulsed laser deposition.X-ray diffraction patterns indicate that free-standing PZT（95/5） film possesses an α-axis preferred orientation.The critical electric field for the 300-nm-thick free-standing PZT（95/5） film transiting from antiferroelectric to ferroelectric phases is increased to 770 kV/cm,but its saturation polarization remains almost unchanged as compared with that of the substrate-clamped PZT（95/5） film.The energy storage density and energy efficiency of the substrate-clamped PZT（95/5） film are 6.49 J/cm^3 and 54.5%,respectively.In contrast,after removing the substrate,the energy storage density and energy efficiency of the free-standing PZT（95/5） film are enhanced up to 17.45 J/cm^3 and 67.9%,respectively.展开更多
This paper investigates the pyroelectric of poled antiferroelectric （AFE） ceramic Pbo.97Lao.02 （Zro.69Sno.196 Ti0.114）03 and its remnant polarization dependence of hydrostatic pressure. The results show that the b...This paper investigates the pyroelectric of poled antiferroelectric （AFE） ceramic Pbo.97Lao.02 （Zro.69Sno.196 Ti0.114）03 and its remnant polarization dependence of hydrostatic pressure. The results show that the bound charges of poled sample can be released in short time by temperature field or pressure field. The released charge abruptly forms a large pulse current. The phenomena of released charge under external fields result in the ferroelectric-AFE phase transition induced by temperature or hydrostatic pressure.展开更多
A new type of large\|displacement actuator called RAINBOW (Reduced And Internally Biased Oxide Wafer) was fabricated by a chemical reduction of PSZT antiferroelectric ceramic. It is found that PSZT was easily reduced ...A new type of large\|displacement actuator called RAINBOW (Reduced And Internally Biased Oxide Wafer) was fabricated by a chemical reduction of PSZT antiferroelectric ceramic. It is found that PSZT was easily reduced and the optimal conditions for producing RAINBOW samples were determined to be 870℃ for 2~3 h. The AFE\|FE phase transitions occur at lower field strength in RAINBOWs compared with normal PSZT. Larger axial displacement (about 190μm) was obtained from the RAINBOWs by application of electric ...展开更多
Relaxor ferroic dielectrics have garnered increasing attention in the past decade as promising materials for energy storage.Among them,relaxor antiferroelectrics(AFEs)and relaxor ferroelectrics(FEs)have shown great pr...Relaxor ferroic dielectrics have garnered increasing attention in the past decade as promising materials for energy storage.Among them,relaxor antiferroelectrics(AFEs)and relaxor ferroelectrics(FEs)have shown great promise in term of high energy storage density and efficiency,respectively.In this study,a unique phase transition from relaxor AFE to relaxor FE was achieved for the first time by introducing strong-ferroelectricity BaTiO_(3)into NaNbO_(3)-BiFeO_(3)system,leading to an evolution from AFE R hierarchical nanodomains to FE polar nanoregions.A novel medium state,consisting of relaxor AFE and relaxor FE,was identified in the crossover of 0.88NaNbO_(3)–0.07BiFeO_(3)–0.05BaTiO_(3)ceramic,exhibiting a distinctive core-shell grain structure due to the composition segregation.By harnessing the advantages of high energy storage density from relaxor AFE and large efficiency from relaxor FE,the ceramic showcased excellent overall energy storage properties.It achieved a substantial recoverable energy storage density W_(rec)~13.1 J/cm^(3)and an ultrahigh efficiencyη~88.9%.These remarkable values shattered the trade-off relationship typically observed in most dielectric capacitors between W_(rec)andη.The findings of this study provide valuable insights for the design of ceramic capacitors with enhanced performance,specifically targeting the development of next generation pulse power devices.展开更多
As a close relative of ferroelectricity,antiferroelectricity has received a recent resurgence of interest driven by technological aspirations in energy-efficient applications,such as energy storage capacitors,solid-st...As a close relative of ferroelectricity,antiferroelectricity has received a recent resurgence of interest driven by technological aspirations in energy-efficient applications,such as energy storage capacitors,solid-state cooling devices,explosive energy conversion,and displacement transducers.Though prolonged efforts in this area have led to certain progress and the discovery of more than 100 antiferroelectric materials over the last 70 years,some scientific and technological issues remain unresolved.Herein,we provide perspectives on the development of antiferroelectrics for energy storage and conversion applications,as well as a comprehensive understanding of the structural origin of antiferroelectricity and field-induced phase transitions,followed by design strategies for new lead-free antiferroelectrics.We also envision unprecedented challenges in the development of promising antiferroelectric materials that bridge materials design and real applications.Future research in these directions will open up new possibilities in resolving the mystery of antiferroelectricity,provide opportunities for comprehending structure-property correlation and developing antiferroelectric/ferroelectric theories,and suggest an approach to the manipulation of phase transitions for real-world applications.展开更多
The electric field-induced irreversible domain wall motion results in a ferroelectric(FE) hysteresis. In antiferroelectrics(AFEs), the irreversible phase transition is the main reason for the hysteresis effects, which...The electric field-induced irreversible domain wall motion results in a ferroelectric(FE) hysteresis. In antiferroelectrics(AFEs), the irreversible phase transition is the main reason for the hysteresis effects, which plays an important role in energy storage performance. Compared to the well-demonstrated FE hysteresis,the structural mechanism of the hysteresis in AFE is not well understood. In this work, the underlying correlation between structure and the hysteresis effect is unveiled in Pb(Zr,Sn,Ti)O_(3) AFE system by using in-situ electrical biasing synchrotron X-ray diffraction. It is found that the AFE with a canting dipole configuration, which shows a continuous polarization rotation under the electric field, tends to have a small hysteresis effect. It presents a negligible phase transition, a small axis ratio, and electric field-induced lattice changing, small domain switching. All these features together lead to a slim hysteresis loop and a high energy storage efficiency. These results offer a deep insight into the structure-hysteresis relationship of AFEs and are helpful for the design of energy storage material.展开更多
The switching behavior of antiferroelectric domain structures under the applied electric field is not fully understood.In this work,by using the phase field simulation,we have studied the polarization switching proper...The switching behavior of antiferroelectric domain structures under the applied electric field is not fully understood.In this work,by using the phase field simulation,we have studied the polarization switching property of antiferroelectric domains.Our results indicate that the ferroelectric domains nucleate preferably at the boundaries of the antiferroelectric domains,and antiferroelectrics with larger initial domain sizes possess a higher coercive electric field as demonstrated by hysteresis loops.Moreover,we introduce charge defects into the sample and numerically investigate their influence.It is also shown that charge defects can induce local ferroelectric domains,which could suppress the saturation polarization and narrow the enclosed area of the hysteresis loop.Our results give insights into understanding the antiferroelectric phase transformation and optimizing the energy storage property in experiments.展开更多
A new type of large-displacement actuator called reduced and internally biased oxide wafer （RAINBOW） is fabricated by chemical reduction of Pb（Sn, Zr, Ti）O3（PSZT） antiferroelectric ceramics and its properties ar...A new type of large-displacement actuator called reduced and internally biased oxide wafer （RAINBOW） is fabricated by chemical reduction of Pb（Sn, Zr, Ti）O3（PSZT） antiferroelectric ceramics and its properties are investigated. It is found that PSZT is easily reduced and the optimal conditions for producing RAINBOW samples are determined to be 870 ℃ for 2-3 h. The antiferroelectrics-ferroelectrics phase transitions occur at lower field strength in RAINBOW actuators compared with normal PSZT actuators. Large axial displacements are also obtained from the RAINBOW actuator by application of electric fields exceeding the phase switching level. However, the field-induced displacement of the RAINBOW actuator is dependent on the manner of applying load on the samples.展开更多
Pb0.97La0.02Zr0.95Ti0.05O3(PLZT)antiferroelectric thick films derived from different precursor solution concentrations are prepared on platinized silicon substrates by sol-gel processing.The films present polycrystall...Pb0.97La0.02Zr0.95Ti0.05O3(PLZT)antiferroelectric thick films derived from different precursor solution concentrations are prepared on platinized silicon substrates by sol-gel processing.The films present polycrystalline perovskite structure with a(100)preferred orientation by X-ray diffraction(XRD)analysis.The antiferroelectricity of the films is confirmed by the double hysteresis behaviors of polarization and double-bufferfly response of dielectric constant under the applied electrical field.Antiferroelectric properties and dielectric constant are improved while the polarization characteristic values are reduced with the increase of precursor solution concentration.The films at higher precursor solution concentration exhibit excellent dielectric properties.展开更多
The reported electrocaloric(EC)effect in ferroelectrics is poised for application in the next generation of solidstate refrigeration technology,exhibiting substantial developmental potential.This study introduces a no...The reported electrocaloric(EC)effect in ferroelectrics is poised for application in the next generation of solidstate refrigeration technology,exhibiting substantial developmental potential.This study introduces a novel and efficient EC effect strategy in(1-x)Pb(Lu_(1/2)Nb_(1/2))O_(3)-xPbTiO_(3)(PLN-xPT)ceramics for low electric-fielddriven devices.Phase-field simulations provide fundamental insights into thermally induced continuous phase transitions,guiding subsequent experimental investigations.A comprehensive composition/temperature-driven phase evolution diagram is constructed,elucidating the sequential transformation from ferroelectric(FE)to antiferroelectric(AFE)and finally to paraelectric(PE)phases for x=0.10-0.18 components.Direct measurements of EC performance highlight x=0.16 as an outstanding performer,exhibiting remarkable properties,including an adiabatic temperature change(ΔT)of 3.03 K,EC strength(ΔT/ΔE)of 0.08 K cm kV-1,and a temperature span(Tspan)of 31℃.The superior EC effect performance is attributed to the temperature-induced FE to AFE transition at low electric fields and diffusion phase transition behavior contributing to the wide Tspan.This work provides valuable insights into developing high-performance EC effect across broad temperature ranges through the strategic design of continuous phase transitions,offering a simplified and economical approach for advancing ecofriendly and efficient solid-state cooling technologies.展开更多
The structural phase transitions and ferroelectric dynamics of lead-free AgNbO_(3)have attracted consid-erable attention owing to their potential in energy-storage device applications.Here,we examine the impact of Li+...The structural phase transitions and ferroelectric dynamics of lead-free AgNbO_(3)have attracted consid-erable attention owing to their potential in energy-storage device applications.Here,we examine the impact of Li+doping on the phase transitions and polarization behavior of(Ag_(1-x)Li_(x))NbO_(3)(x=0-7%)ceramics through comprehensive dielectric and ferroelectric analyses.Rietveld refinement reveals a Li+-induced phase transition from Pbcm to R3c,with x=5%and x=6%compositions near the morphotropic phase boundary(MPB).Dielectric anomalies identify key characteristic temperatures,supporting the con-struction of a low-field phase diagram.High-field studies uncover a direct relationship between phase structure and polarization behavior,culminating in a high-field phase diagram.Near-MPB compositions exhibit distinct structural states,elucidating the mechanisms of reversible and irreversible phase transi-tions.This work provides a comprehensive explanation of the evolution of hysteresis loop profiles,capturing their progression from double hysteresis loops to square loops and their subsequent reversion to double loops under varying electric field and temperature conditions.These temperature-composition(T-x)and temperature-electric field(T-E)phase diagrams provide a robust framework for understanding phase evolution,offering critical insights into optimizing AgNbO_(3)-based ceramics for advanced functional applications.展开更多
Antiferroelectric(AFE)materials have received great attention because of their potential applications in the energy sector.Nevertheless,the properties of AFE materials have not been explored for a long time,especially...Antiferroelectric(AFE)materials have received great attention because of their potential applications in the energy sector.Nevertheless,the properties of AFE materials have not been explored for a long time,especially the atomic-scale understanding of AFE domain walls.Here,using first-principles-based machine learning potentials,we identify the atomic structures,energies,and dynamic properties of the domain walls for AFE lead zirconate.It is found that the domain wall can reduce the critical antiferroelectric-ferroelectric transition field.During the electric field-driven polarization switching process,the domain wall is immobile.Importantly,we observe that a distinct domain structure spontaneously forms in bulk lead zirconate upon annealing at 300 K.The domain structure exhibits an alternating array of clockwise–anticlockwise vortexes along radial with continuous polarization rotation.This anomalous AFE vortex is derived from the energy degeneracy in four possible orientations of the polarization order,which can enhance the dielectric response in the terahertz.The current results give an implication for the emergence of AFE vortex in AFE materials as well as ferroelectric materials.展开更多
文摘Multiferroics, having both magnetic and electric orders withina single material, have been extensively studied for academiccuriosity and possible applications, including energy-efficientmemory and logic devices [1–3]. Although several multiferroicmaterials have been reported for bulk single crystals, recentinterest has shifted towards atomically thin magnetic materials.Achieving multiferroic at the limit of few or single atomic layershas become a significant challenging [4,5].
基金supported by the National Natural Science Foun-dation of China(Grant Nos.U2002217,11774366 and 52102342).
文摘Due to the atomic-level centrosymmetric spontaneous polarization,antiferroelectric materials exhibit a sensitively nonlinear capacitive response to plural physic fields(mainly electric field and temperature)in a certain range,consequently leading to some superb material properties,e.g.,ripple suppression,elec-trocaloric cooling,and dielectric energy storage.However,there are many cognitive blanks about how this exotic multi-field relationε(E_(DC),T)is influenced and manipulated via microscopic structures in the anti-ferroelectrics.In this work,the classic antiferroelectric ceramics PLZT were selected to see this intelligent effect,based on a quad-parameterizedε(E_(DC))relation on the dependence of T.εrelations were studied under different material compositions,temperature,frequency,AC electric field,and DC electric field,re-vealing lattice/domain structure evolution and the underlying mechanism.The inherent phase stability,introduced random field,and hierarchical hysteresis states were found to co-dominate this multi-field nonlinear relation.This work would not only contribute to future progress in the current applications(ripple suppression/electrocaloric cooling/dielectric energy storage)but imply the possibility of co-sensing temperature and electric potential simply and smartly.
文摘Reduced and internally biased oxide wafer (RAINBOW) Pb (Sn, Zr, Ti) O3 (PSZT) antiferroelectric ceramics are fabricated by chemical reduction. It is a kind of large displacement actuating materials composed of reduced and unreduced layers. It is found that PSZT is easily reduced and the optimal conditions for producing RAINBOW samples are determined to be 870°C for 2 to 3 h, which results in a reduced layer composed of metallic lead and refractory oxides (PbO, ZrO2 and ZrTiO4). The phase transitions from antiferroelectric state to ferroelectric state occur at lower field strength in RAINBOW samples compared with normal PSZT ceramics. Larger axial displacement is also obtained from RAINBOW samples by application of electric fields exceeding the phase switching level. However, the actuating properties of RAINBOW samples are dependent on the manner of applying load on it.
基金supported by the National Natural Science Foundation of China(Grant Nos.51202273,11204304,and 11304334)the Science and Technology Commission of Shanghai Municipality,China(Grant No.14DZ2261000)
文摘The phase transitions, dielectric properties, and polarization versus electric field （P-E） hysteresis loops of Pbo.97Lao.02（Zr0.42Sn0.58-xTix）O3 （0.13≤ x ≤0.18） （PLZST） bulk ceramics were systematically investigated. This study exhibited a sequence of phase transitions by analyzing the change of the P-E hysteresis loops with increasing temperature. The anfiferroelectric （AFE） to ferroelectric （FE） phase boundary of PLZST with the Zr content of 0.42 was found to locate at the Ti content between 0.14 and 0.15. This work is aimed to improve the ternary phase diagram of lanthanum-doped PZST with the Zr content of 0.42 and will be a good reference for seeking high energy storage density in the PLZST system with low-Zr content.
基金This work was supported by the National Natural Science Foundation of China under grant No.1998061408.
文摘The crystal and electronic structure of antiferroelectric squaric acid is studied using density functional theory method, and the exchange correlation effects are treated by the generalized approximation. In order to understand the ferroelectricity of H2SQ in the molecular plane and the antiferroelectricity in whole crystal, the density of states, charge density distribution and band structure are calculated. The result showed that O2p and C2p play important roles in the interactions between layers. The hybridizations of 02s-Hls and 02p-Hls are responsible for the tendency to ferroelectricity within each layer.
文摘The complex dielectric constant of pure and cerium doped calcium-barium-niobate (CBN) was studied at frequencies 20 Hz ≤ f ≤ 1 MHz in the temperature range 300 K ≤ T ≤ 650 K and compared with the results for the well known ferroelectric relaxor strontium-barium-niobate (SBN). By the analysis of the systematically taken temperature and frequency dependent measurements of the dielectric constant the phase transition characteristic of the investigated materials was evaluated. From the results it must be assumed that CBN shows a slightly diffuse phase transition without relaxor behavior. Doping with cerium yields a definitely different phase transition characteristic with some indications for a relaxor type ferroelectric material, which are common from SBN.
基金financially supported by the National Natural Science Foundation of China(Nos.52073144,51802068)the Natural Science Foundation of Hebei Province,China(No.E2021201044)+2 种基金the Natural Science Foundation of Jiangsu Province,China(No.BK20201301)Qing Lan Project,the State Key Laboratory of New Ceramic and Fine Processing Tsinghua University(Nos.KF202005,KF202114)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Antiferroelectric materials are promising candidates for energy-storage applications due to their double hysteresis loops,which can deliver high power density.Among the antiferroelectric materials,AgNbO_(3)is proved attractive due to its environmental-friendliness and high potential for achieving excellent energy storage performance.However,the recoverable energy storage density of AgNbO_(3)ceramics is limited by their relatively low breakdown strength.Herein,the breakdown strength of the pure AgNbO_(3)ceramics prepared using the tape casting method is enhanced to 307 kV·cm^(-1),which is,to the best of our knowledge,among the highest values reported for pure AgNbO-3bulk ceramics.The high breakdown strength may be due to its dense microstructure and good crystallinity obtained by the tape casting method and the optimized sintering temperature.Owing to its enhanced breakdown strength,AgNbO_(3)ceramics show high recoverable energy storage density of 2.8 J·cm^(-3).These results have led to the development of lead-free antiferroelectric materials and devices with high energy storage density.
基金Project supported by the National Basic Research Program of China (Grant No.2009CB623306)the International Science & Technology Cooperation Program of China (Grant No.2010DFR50480)the National Natural Science Foundation of China (Grant No.10976022)
文摘Antiferroelectric ferroelectric （AFE-FE） phase transition in ceramic Pbo.97Lao.02（Zro.75Snon36Tion14）O3 （PLZST） was studied by dielectric spectroscopy as functions of frequency （102-105 Hz） and pressure （0-500 MPa） under a DC electric field. The hydrostatic pressure-dependent remnant polarization and dielectric constant were mea- sured. The results show that remnant polarization of the metastable rhombohedral ferroelectric PLZST poled ceramic decreases sharply and depoles completely at phase transition under hydrostatic pressure. The dielectric constant um dergoes an abrupt jump twice during a load and unload cycle under an electric field. The two abrupt jumps correspond to two phase transitions, FE AFE and AFE-FE.
基金supported by the National Natural Science Foundation of China(Grant Nos.11374312,51401230,and 51522105)the Fund for Ningbo Municipal Science and Technology Innovation Team,China(Grant No.2015B11001)
文摘Free-standing antiferroelectric Pb（Zr0.95Ti0.05O3（PZT（95/5）） thin film is fabricated on 200-nm-thick Pt foil by using pulsed laser deposition.X-ray diffraction patterns indicate that free-standing PZT（95/5） film possesses an α-axis preferred orientation.The critical electric field for the 300-nm-thick free-standing PZT（95/5） film transiting from antiferroelectric to ferroelectric phases is increased to 770 kV/cm,but its saturation polarization remains almost unchanged as compared with that of the substrate-clamped PZT（95/5） film.The energy storage density and energy efficiency of the substrate-clamped PZT（95/5） film are 6.49 J/cm^3 and 54.5%,respectively.In contrast,after removing the substrate,the energy storage density and energy efficiency of the free-standing PZT（95/5） film are enhanced up to 17.45 J/cm^3 and 67.9%,respectively.
基金supported by the National Basic Research Program of China (973 Program) (Grant No. 2009CB623306)the National Natural Science Foundation of China (Grant No. 60528008)+1 种基金the Key Science and Technology Research Project from the Ministry of Education of China (Grant No. 108180)the National Natural Science Foundation of China-NSAF (Grant No. 10976022)
文摘This paper investigates the pyroelectric of poled antiferroelectric （AFE） ceramic Pbo.97Lao.02 （Zro.69Sno.196 Ti0.114）03 and its remnant polarization dependence of hydrostatic pressure. The results show that the bound charges of poled sample can be released in short time by temperature field or pressure field. The released charge abruptly forms a large pulse current. The phenomena of released charge under external fields result in the ferroelectric-AFE phase transition induced by temperature or hydrostatic pressure.
基金National Natural Science F oundation of China(5 990 2 0 0 2 ) Aeronautical Science F oundation(99G5 2 0 65 )
文摘A new type of large\|displacement actuator called RAINBOW (Reduced And Internally Biased Oxide Wafer) was fabricated by a chemical reduction of PSZT antiferroelectric ceramic. It is found that PSZT was easily reduced and the optimal conditions for producing RAINBOW samples were determined to be 870℃ for 2~3 h. The AFE\|FE phase transitions occur at lower field strength in RAINBOWs compared with normal PSZT. Larger axial displacement (about 190μm) was obtained from the RAINBOWs by application of electric ...
基金financially supported by the National Natural Science Foundation of China(Nos.52172181,22105017)Interdisciplinary Research Project for Young Teachers of USTB(No.FRFIDRY-21–002)。
文摘Relaxor ferroic dielectrics have garnered increasing attention in the past decade as promising materials for energy storage.Among them,relaxor antiferroelectrics(AFEs)and relaxor ferroelectrics(FEs)have shown great promise in term of high energy storage density and efficiency,respectively.In this study,a unique phase transition from relaxor AFE to relaxor FE was achieved for the first time by introducing strong-ferroelectricity BaTiO_(3)into NaNbO_(3)-BiFeO_(3)system,leading to an evolution from AFE R hierarchical nanodomains to FE polar nanoregions.A novel medium state,consisting of relaxor AFE and relaxor FE,was identified in the crossover of 0.88NaNbO_(3)–0.07BiFeO_(3)–0.05BaTiO_(3)ceramic,exhibiting a distinctive core-shell grain structure due to the composition segregation.By harnessing the advantages of high energy storage density from relaxor AFE and large efficiency from relaxor FE,the ceramic showcased excellent overall energy storage properties.It achieved a substantial recoverable energy storage density W_(rec)~13.1 J/cm^(3)and an ultrahigh efficiencyη~88.9%.These remarkable values shattered the trade-off relationship typically observed in most dielectric capacitors between W_(rec)andη.The findings of this study provide valuable insights for the design of ceramic capacitors with enhanced performance,specifically targeting the development of next generation pulse power devices.
基金the Fundamental Research Funds for the Central Universities(University of Science and Technology Beijing:No.06500135)the Alexander von Humboldt Foundation for financial support+3 种基金support from the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIPNo.2019R1I1A1A01063888)USTB MatCom of Beijing Advanced Innovation Center for Materials Genome Engineeringthe financial supports of the PolyU Post-Dr Research Grant(No.G-YW5T)from The Hong Kong Polytechnic University。
文摘As a close relative of ferroelectricity,antiferroelectricity has received a recent resurgence of interest driven by technological aspirations in energy-efficient applications,such as energy storage capacitors,solid-state cooling devices,explosive energy conversion,and displacement transducers.Though prolonged efforts in this area have led to certain progress and the discovery of more than 100 antiferroelectric materials over the last 70 years,some scientific and technological issues remain unresolved.Herein,we provide perspectives on the development of antiferroelectrics for energy storage and conversion applications,as well as a comprehensive understanding of the structural origin of antiferroelectricity and field-induced phase transitions,followed by design strategies for new lead-free antiferroelectrics.We also envision unprecedented challenges in the development of promising antiferroelectric materials that bridge materials design and real applications.Future research in these directions will open up new possibilities in resolving the mystery of antiferroelectricity,provide opportunities for comprehending structure-property correlation and developing antiferroelectric/ferroelectric theories,and suggest an approach to the manipulation of phase transitions for real-world applications.
基金supported by the National Natural Science Foundation of China (Nos.22235002, 21825102 and 12004032)the Advanced Photon Source at Argonne National Laboratory was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No.DEAC02–06CH11357。
文摘The electric field-induced irreversible domain wall motion results in a ferroelectric(FE) hysteresis. In antiferroelectrics(AFEs), the irreversible phase transition is the main reason for the hysteresis effects, which plays an important role in energy storage performance. Compared to the well-demonstrated FE hysteresis,the structural mechanism of the hysteresis in AFE is not well understood. In this work, the underlying correlation between structure and the hysteresis effect is unveiled in Pb(Zr,Sn,Ti)O_(3) AFE system by using in-situ electrical biasing synchrotron X-ray diffraction. It is found that the AFE with a canting dipole configuration, which shows a continuous polarization rotation under the electric field, tends to have a small hysteresis effect. It presents a negligible phase transition, a small axis ratio, and electric field-induced lattice changing, small domain switching. All these features together lead to a slim hysteresis loop and a high energy storage efficiency. These results offer a deep insight into the structure-hysteresis relationship of AFEs and are helpful for the design of energy storage material.
基金Project supported by the Natural Science Foundation of Jiangsu Province of China(Grant No.BK20190405)the LOEWE program of the State of Hesse,Germany,within the project FLAME(Fermi Level Engineering of Antiferroelectric Materials for Energy Storage and Insulation Systems)。
文摘The switching behavior of antiferroelectric domain structures under the applied electric field is not fully understood.In this work,by using the phase field simulation,we have studied the polarization switching property of antiferroelectric domains.Our results indicate that the ferroelectric domains nucleate preferably at the boundaries of the antiferroelectric domains,and antiferroelectrics with larger initial domain sizes possess a higher coercive electric field as demonstrated by hysteresis loops.Moreover,we introduce charge defects into the sample and numerically investigate their influence.It is also shown that charge defects can induce local ferroelectric domains,which could suppress the saturation polarization and narrow the enclosed area of the hysteresis loop.Our results give insights into understanding the antiferroelectric phase transformation and optimizing the energy storage property in experiments.
基金This project is supported by National Natural Science Foundation of China (No.50135030)Aeronautical Science Foundation of China(No.04G52042)Pre-research fund of Weapons & Equipments of China(No.51412010505HK0208).
文摘A new type of large-displacement actuator called reduced and internally biased oxide wafer （RAINBOW） is fabricated by chemical reduction of Pb（Sn, Zr, Ti）O3（PSZT） antiferroelectric ceramics and its properties are investigated. It is found that PSZT is easily reduced and the optimal conditions for producing RAINBOW samples are determined to be 870 ℃ for 2-3 h. The antiferroelectrics-ferroelectrics phase transitions occur at lower field strength in RAINBOW actuators compared with normal PSZT actuators. Large axial displacements are also obtained from the RAINBOW actuator by application of electric fields exceeding the phase switching level. However, the field-induced displacement of the RAINBOW actuator is dependent on the manner of applying load on the samples.
基金National Natural Science Foundation of China(No.60806039,No.51175483)China Postdoctoral Science Foundation Projects(No.20090461275,No.201003658)+1 种基金Shanxi Provincial Natural Science Foundation of China(No.20100210023-6)Shanxi Provincial Young Leaders on Science
文摘Pb0.97La0.02Zr0.95Ti0.05O3(PLZT)antiferroelectric thick films derived from different precursor solution concentrations are prepared on platinized silicon substrates by sol-gel processing.The films present polycrystalline perovskite structure with a(100)preferred orientation by X-ray diffraction(XRD)analysis.The antiferroelectricity of the films is confirmed by the double hysteresis behaviors of polarization and double-bufferfly response of dielectric constant under the applied electrical field.Antiferroelectric properties and dielectric constant are improved while the polarization characteristic values are reduced with the increase of precursor solution concentration.The films at higher precursor solution concentration exhibit excellent dielectric properties.
基金financially supported by the National Natural Science Foundation of China(Grant No.52261135548)the Key Research and Development Program of Shaanxi(Program No.2022KWZ-22)+2 种基金The research was made possible by Russian Science Foundation(Project No.23-42-00116)The equipment of the Ural Center for Shared Use“Modern nanotechnology”Ural Federal University(Reg.No.2968)which is supported by the Ministry of ScienceHigher Education RF(Project No.075-15-2021-677)was used.
文摘The reported electrocaloric(EC)effect in ferroelectrics is poised for application in the next generation of solidstate refrigeration technology,exhibiting substantial developmental potential.This study introduces a novel and efficient EC effect strategy in(1-x)Pb(Lu_(1/2)Nb_(1/2))O_(3)-xPbTiO_(3)(PLN-xPT)ceramics for low electric-fielddriven devices.Phase-field simulations provide fundamental insights into thermally induced continuous phase transitions,guiding subsequent experimental investigations.A comprehensive composition/temperature-driven phase evolution diagram is constructed,elucidating the sequential transformation from ferroelectric(FE)to antiferroelectric(AFE)and finally to paraelectric(PE)phases for x=0.10-0.18 components.Direct measurements of EC performance highlight x=0.16 as an outstanding performer,exhibiting remarkable properties,including an adiabatic temperature change(ΔT)of 3.03 K,EC strength(ΔT/ΔE)of 0.08 K cm kV-1,and a temperature span(Tspan)of 31℃.The superior EC effect performance is attributed to the temperature-induced FE to AFE transition at low electric fields and diffusion phase transition behavior contributing to the wide Tspan.This work provides valuable insights into developing high-performance EC effect across broad temperature ranges through the strategic design of continuous phase transitions,offering a simplified and economical approach for advancing ecofriendly and efficient solid-state cooling technologies.
基金finically supported by the National Natural Science Foundation of China(Nos.52261135548,52302153,and 52402155)the China Postdoctoral Science Foundation(Nos.GZC20232075 and 2023M742767)+2 种基金The research was made possible by Russian Science Foundation(Project No 23-42-00116)The equipment of the Ural Center for Shared Use“Modern nanotech-nology”Ural Federal University(Reg.No2968)whichis supported by the Ministry of Science and Higher Education RF(Project No 075-15-2021-677)was usedThe SEM work was done at International Center for Dielectric Research(ICDR),Xi’an Jiaotong University,Xi’an,China.
文摘The structural phase transitions and ferroelectric dynamics of lead-free AgNbO_(3)have attracted consid-erable attention owing to their potential in energy-storage device applications.Here,we examine the impact of Li+doping on the phase transitions and polarization behavior of(Ag_(1-x)Li_(x))NbO_(3)(x=0-7%)ceramics through comprehensive dielectric and ferroelectric analyses.Rietveld refinement reveals a Li+-induced phase transition from Pbcm to R3c,with x=5%and x=6%compositions near the morphotropic phase boundary(MPB).Dielectric anomalies identify key characteristic temperatures,supporting the con-struction of a low-field phase diagram.High-field studies uncover a direct relationship between phase structure and polarization behavior,culminating in a high-field phase diagram.Near-MPB compositions exhibit distinct structural states,elucidating the mechanisms of reversible and irreversible phase transi-tions.This work provides a comprehensive explanation of the evolution of hysteresis loop profiles,capturing their progression from double hysteresis loops to square loops and their subsequent reversion to double loops under varying electric field and temperature conditions.These temperature-composition(T-x)and temperature-electric field(T-E)phase diagrams provide a robust framework for understanding phase evolution,offering critical insights into optimizing AgNbO_(3)-based ceramics for advanced functional applications.
基金supported by the National Natural Science Foundation of China(Grant Nos.92477114,12204496,and 12422407)the Zhejiang Provincial Natural Science Foundation(Grant No.Q23A040003)the Ningbo Natural Science Foundation(No.2023J360).
文摘Antiferroelectric(AFE)materials have received great attention because of their potential applications in the energy sector.Nevertheless,the properties of AFE materials have not been explored for a long time,especially the atomic-scale understanding of AFE domain walls.Here,using first-principles-based machine learning potentials,we identify the atomic structures,energies,and dynamic properties of the domain walls for AFE lead zirconate.It is found that the domain wall can reduce the critical antiferroelectric-ferroelectric transition field.During the electric field-driven polarization switching process,the domain wall is immobile.Importantly,we observe that a distinct domain structure spontaneously forms in bulk lead zirconate upon annealing at 300 K.The domain structure exhibits an alternating array of clockwise–anticlockwise vortexes along radial with continuous polarization rotation.This anomalous AFE vortex is derived from the energy degeneracy in four possible orientations of the polarization order,which can enhance the dielectric response in the terahertz.The current results give an implication for the emergence of AFE vortex in AFE materials as well as ferroelectric materials.
