Emerging new applications of antiferroelectric perovskite oxides based on their fascinating phase transformation between polar and nonpolar states have provided considerable attention to this class of materials even d...Emerging new applications of antiferroelectric perovskite oxides based on their fascinating phase transformation between polar and nonpolar states have provided considerable attention to this class of materials even decades after the discovery of antiferroelectricity.After presenting the challenge of formulating a precise definition of antiferroelectric materials,we briefly summarize proposed applications.In the following,we focus on the crystallographic structures of the antiferroelectric and ferroelectric phases of NaNbO_(3),which is emerging as a promising alternative to PbZrO_(3)-based systems.The field-induced phase transition behavior of NaNbO_(3)-based AFE materials in the form of single crystals,bulk ceramics,and multilayer ceramic capacitors is reviewed.Recent advances in a group of materials exhibiting high energy storage performance and relaxor-like behavior are also covered.The influence of electrode geometry on phase transition behavior and thus on the energy storage property is briefly addressed.The review concludes with an overview of the remaining challenges related to the fundamental understanding of the scientific richness of AFE materials in terms of structure,microstructure,defect transport under high fields,and phase transition dynamics required for their future development and applications.展开更多
The recent review for the Restriction of Hazardous Substances Directive(RoHS)by the expert committee,appointed by the European Union,stated that the replacement of PZT“…may be scientifically and technologically prac...The recent review for the Restriction of Hazardous Substances Directive(RoHS)by the expert committee,appointed by the European Union,stated that the replacement of PZT“…may be scientifically and technologically practical to a certain degree…”,although replacement“…is scientifically and technically still impractical in the majority of applications.”Thus,two decades of sustained research and development may be approaching fruition,at first limited to a minority of applications.Therefore,it is of paramount importance to assess the viability of lead-free piezoceramics over a broad range of application-relevant properties.These are identified and discussed in turn:1.Cost,2.Reproducibility,3.Mechanical and Thermal Properties,4.Electrical Conductivity,and 5.Lifetime.It is suggested that the worldwide efforts into the development of lead-free piezoceramics now require a broader perspective to bring the work to the next stage of development by supporting implementation into real devices.Guidelines about pertinent research requirements into a wide range of secondary properties,measurement techniques,and salient literature are provided.展开更多
Lead-free piezoceramics based on the(Ba,Ca)(Zr,Ti)O3(BCZT) system exhibit excellent electromechanical properties for low-temperature actuation applications, but suffer from relatively high processing temperatures. Her...Lead-free piezoceramics based on the(Ba,Ca)(Zr,Ti)O3(BCZT) system exhibit excellent electromechanical properties for low-temperature actuation applications, but suffer from relatively high processing temperatures. Here we demonstrate an approach for the reduction of the sintering temperature and simultaneous increase of the electromechanical strain response of(Ba,Ca)(Zr,Ti)O3 piezoceramics by aliovalent doping with Ce. The samples were prepared by solid state synthesis and their crystallographic structure, dielectric, ferroelectric, and electromechanical properties were investigated. The highest d33* value of 1189 pm/V was obtained for the sample with 0.05 mol% Ce, substituted on the A-site of the perovskite lattice. The results indicate a large potential of these materials for off-resonance piezoelectric actuators.展开更多
基金This work was supported by the Hessian State Ministry for Higher Education,Research and the Arts under the LOEWE collaborative project FLAME(Fermi level engineering of antiferro-electric materials for energy storage and insulation systems).
文摘Emerging new applications of antiferroelectric perovskite oxides based on their fascinating phase transformation between polar and nonpolar states have provided considerable attention to this class of materials even decades after the discovery of antiferroelectricity.After presenting the challenge of formulating a precise definition of antiferroelectric materials,we briefly summarize proposed applications.In the following,we focus on the crystallographic structures of the antiferroelectric and ferroelectric phases of NaNbO_(3),which is emerging as a promising alternative to PbZrO_(3)-based systems.The field-induced phase transition behavior of NaNbO_(3)-based AFE materials in the form of single crystals,bulk ceramics,and multilayer ceramic capacitors is reviewed.Recent advances in a group of materials exhibiting high energy storage performance and relaxor-like behavior are also covered.The influence of electrode geometry on phase transition behavior and thus on the energy storage property is briefly addressed.The review concludes with an overview of the remaining challenges related to the fundamental understanding of the scientific richness of AFE materials in terms of structure,microstructure,defect transport under high fields,and phase transition dynamics required for their future development and applications.
文摘The recent review for the Restriction of Hazardous Substances Directive(RoHS)by the expert committee,appointed by the European Union,stated that the replacement of PZT“…may be scientifically and technologically practical to a certain degree…”,although replacement“…is scientifically and technically still impractical in the majority of applications.”Thus,two decades of sustained research and development may be approaching fruition,at first limited to a minority of applications.Therefore,it is of paramount importance to assess the viability of lead-free piezoceramics over a broad range of application-relevant properties.These are identified and discussed in turn:1.Cost,2.Reproducibility,3.Mechanical and Thermal Properties,4.Electrical Conductivity,and 5.Lifetime.It is suggested that the worldwide efforts into the development of lead-free piezoceramics now require a broader perspective to bring the work to the next stage of development by supporting implementation into real devices.Guidelines about pertinent research requirements into a wide range of secondary properties,measurement techniques,and salient literature are provided.
基金funded by Ministry of Science,Research and Technology of Iran as a Ph.D.project,with Grant No.481392053,at Materials&Energy Research Center(MERC)supported by Deutsche Forschungsgemeinschaft under the Sonderforschungsbereich 595(SFB 595)fellowship
文摘Lead-free piezoceramics based on the(Ba,Ca)(Zr,Ti)O3(BCZT) system exhibit excellent electromechanical properties for low-temperature actuation applications, but suffer from relatively high processing temperatures. Here we demonstrate an approach for the reduction of the sintering temperature and simultaneous increase of the electromechanical strain response of(Ba,Ca)(Zr,Ti)O3 piezoceramics by aliovalent doping with Ce. The samples were prepared by solid state synthesis and their crystallographic structure, dielectric, ferroelectric, and electromechanical properties were investigated. The highest d33* value of 1189 pm/V was obtained for the sample with 0.05 mol% Ce, substituted on the A-site of the perovskite lattice. The results indicate a large potential of these materials for off-resonance piezoelectric actuators.