The 0.6（Bi1-xLax）FeO 3-0.4SrTiO 3（x = 0,0.1） multiferroic ceramics are prepared by a modified Pechini method to study the effect of substitution of SrTiO3 and La in BiFeO3.The X-ray diffraction patterns confirm th...The 0.6（Bi1-xLax）FeO 3-0.4SrTiO 3（x = 0,0.1） multiferroic ceramics are prepared by a modified Pechini method to study the effect of substitution of SrTiO3 and La in BiFeO3.The X-ray diffraction patterns confirm the single phase characteristics of all the compositions each with a rhombohedral structure.The magnetic properties of the ceramics are significantly improved by a solid solution with SrTiO3 and substitution of La.The values of the dielectric constant ε r and loss tangent tan δ of all the samples decrease with increasing frequency and become constant at room temperature.The La-doped 0.6BiFeO3-0.4SrTiO3 ceramics exhibit improved dielectric and ferroelectric properties,with higher dielectric constant enhanced remnant polarization（Pr） and lower leakage current at room temperature.Compared with a anti-ferromagnetic BiFeO3 compound,the 0.6（Bi0.9La0.1）FeO3-0.4SrTiO3 sample shows the optimal ferromagnetism with remnant magnetization M r ～ 0.135 emμ/g and ferroelectricity with Pr ～ 5.94 μC/cm 2 at room temperature.展开更多
In this paper, multiferroics and magnetocapacitive effect of triangular-lattice antiferromagnet Ag Al0.02Cr0.98S2 are investigated by magnetic, ferroelectric, pyroelectric current and dielectric measurement. We find t...In this paper, multiferroics and magnetocapacitive effect of triangular-lattice antiferromagnet Ag Al0.02Cr0.98S2 are investigated by magnetic, ferroelectric, pyroelectric current and dielectric measurement. We find that it is a multiferroic material and the magnetocapacitive effect reaches a factor of up to 90 in an external field of 7 T. The results imply the further possibility of synthesizing the magnetocapacitive materials by modifying the frustrated spin structure in terms of a few B-site doping nonmagnetic ions.展开更多
Sol-gel process was adopted to prepare BiFeO3 films.BiFeO3 films were deposited on LaNiO3 coated Si（100） substrates annealed at 500 and 550 ℃,respectively.The X-ray diffraction results reveal that BiFeO3 film has a...Sol-gel process was adopted to prepare BiFeO3 films.BiFeO3 films were deposited on LaNiO3 coated Si（100） substrates annealed at 500 and 550 ℃,respectively.The X-ray diffraction results reveal that BiFeO3 film has a rhombohedrally distorted perovskite structure with space group R3c.The film annealed at 500 ℃ has larger remnant polarization（Pr） of 35.3 μC/cm2.For the film annealed at 550 ℃,smaller remnant polarization of Pr=4.8 μC/cm^2 is observed for its low breakdown electric field.Lower leakage conduction is observed in the film annealed at 500 ℃ at low applied field.展开更多
Bismuth ferrite(BFO)nanostructures and thin films have gained attraction as suitable candidates for energy storage and energy conversion due to their high energy storage efficiency,temperature stability and low dielec...Bismuth ferrite(BFO)nanostructures and thin films have gained attraction as suitable candidates for energy storage and energy conversion due to their high energy storage efficiency,temperature stability and low dielectric loss.Electrical properties of such multiferroic materials are tailored by ferroelectric and ferromagnetic constituents and have opened up amazing avenues in elec-trochemical supercapacitor and photovoltaic applications.Dopants play a significant role in optimizing the magnetic and dielec-tric properties of such materials owing to suitable applications.This review highlights the scientific advancements reported in BFO nanostructures for energy applications by optimizing their magnetic and dielectric properties.This paper starts with a brief introduction of BFO and a discussion on the effects of various dopants by different synthesis techniques,and their effects on the magnetic and dielectric properties are also portrayed.Eventually,this review summarizes the various doping effects,which paves way for future research on this multiferroic material.展开更多
The paper discusses the features of the effect of modification with lithium carbonate on the dielectric dispersion of lead ferroniobate ceramics.The modifier has been previously shown to change the ways of the recryst...The paper discusses the features of the effect of modification with lithium carbonate on the dielectric dispersion of lead ferroniobate ceramics.The modifier has been previously shown to change the ways of the recrystallization sintering and therefore reduce the sintering temperature of the ceramics,increase their average grain size,and improve their dielectric and piezoelectric properties.In this study,the emphasis is placed on the analysis of the diffusion effects of the ferroelectric phase transition upon such mod-ification considered from the standpoint of the chemical specifics of the modifier and its location in the structure of the parent compound.展开更多
基金Project supported by the Science Foundation from the Ministry of Education,China (Grant Nos. 20090142120069 and 309020)the Special Scientific Foundation from the Chinese Central University (Grant No. 20102D006)
文摘The 0.6（Bi1-xLax）FeO 3-0.4SrTiO 3（x = 0,0.1） multiferroic ceramics are prepared by a modified Pechini method to study the effect of substitution of SrTiO3 and La in BiFeO3.The X-ray diffraction patterns confirm the single phase characteristics of all the compositions each with a rhombohedral structure.The magnetic properties of the ceramics are significantly improved by a solid solution with SrTiO3 and substitution of La.The values of the dielectric constant ε r and loss tangent tan δ of all the samples decrease with increasing frequency and become constant at room temperature.The La-doped 0.6BiFeO3-0.4SrTiO3 ceramics exhibit improved dielectric and ferroelectric properties,with higher dielectric constant enhanced remnant polarization（Pr） and lower leakage current at room temperature.Compared with a anti-ferromagnetic BiFeO3 compound,the 0.6（Bi0.9La0.1）FeO3-0.4SrTiO3 sample shows the optimal ferromagnetism with remnant magnetization M r ～ 0.135 emμ/g and ferroelectricity with Pr ～ 5.94 μC/cm 2 at room temperature.
基金Project supported by the National Basic Research Program of China(Grant No.2010CB833102)the National Natural Science Foundation of China(Grant Nos.10974244+1 种基金11274369and 11104337)
文摘In this paper, multiferroics and magnetocapacitive effect of triangular-lattice antiferromagnet Ag Al0.02Cr0.98S2 are investigated by magnetic, ferroelectric, pyroelectric current and dielectric measurement. We find that it is a multiferroic material and the magnetocapacitive effect reaches a factor of up to 90 in an external field of 7 T. The results imply the further possibility of synthesizing the magnetocapacitive materials by modifying the frustrated spin structure in terms of a few B-site doping nonmagnetic ions.
基金Funded by the National Natural Science Foundation of China(No.10874075)the Key Program of Hubei Province Education Committee(No. D20082203)
文摘Sol-gel process was adopted to prepare BiFeO3 films.BiFeO3 films were deposited on LaNiO3 coated Si（100） substrates annealed at 500 and 550 ℃,respectively.The X-ray diffraction results reveal that BiFeO3 film has a rhombohedrally distorted perovskite structure with space group R3c.The film annealed at 500 ℃ has larger remnant polarization（Pr） of 35.3 μC/cm2.For the film annealed at 550 ℃,smaller remnant polarization of Pr=4.8 μC/cm^2 is observed for its low breakdown electric field.Lower leakage conduction is observed in the film annealed at 500 ℃ at low applied field.
文摘Bismuth ferrite(BFO)nanostructures and thin films have gained attraction as suitable candidates for energy storage and energy conversion due to their high energy storage efficiency,temperature stability and low dielectric loss.Electrical properties of such multiferroic materials are tailored by ferroelectric and ferromagnetic constituents and have opened up amazing avenues in elec-trochemical supercapacitor and photovoltaic applications.Dopants play a significant role in optimizing the magnetic and dielec-tric properties of such materials owing to suitable applications.This review highlights the scientific advancements reported in BFO nanostructures for energy applications by optimizing their magnetic and dielectric properties.This paper starts with a brief introduction of BFO and a discussion on the effects of various dopants by different synthesis techniques,and their effects on the magnetic and dielectric properties are also portrayed.Eventually,this review summarizes the various doping effects,which paves way for future research on this multiferroic material.
基金This work was financially supported by the Ministry of Science and Higher Education of the Russian Federation:State Task in the Field of Scientific Activity,Scientific Project No.0852-2020-0032(BAZ0110/20-3-07IF).
文摘The paper discusses the features of the effect of modification with lithium carbonate on the dielectric dispersion of lead ferroniobate ceramics.The modifier has been previously shown to change the ways of the recrystallization sintering and therefore reduce the sintering temperature of the ceramics,increase their average grain size,and improve their dielectric and piezoelectric properties.In this study,the emphasis is placed on the analysis of the diffusion effects of the ferroelectric phase transition upon such mod-ification considered from the standpoint of the chemical specifics of the modifier and its location in the structure of the parent compound.
