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High-sensitivity piezoelectric perovskites for magnetoelectric composites

View Article: PubMed Central - PubMed

ABSTRACT

A highly topical set of perovskite oxides are high-sensitivity piezoelectric ones, among which Pb(Zr,Ti)O3 at the morphotropic phase boundary (MPB) between ferroelectric rhombohedral and tetragonal polymorphic phases is reckoned a case study. Piezoelectric ceramics are used in a wide range of mature, electromechanical transduction technologies like piezoelectric sensors, actuators and ultrasound generation, to name only a few examples, and more recently for demonstrating novel applications like magnetoelectric composites. In this case, piezoelectric perovskites are combined with magnetostrictive materials to provide magnetoelectricity as a product property of the piezoelectricity and piezomagnetism of the component phases. Interfaces play a key issue, for they control the mechanical coupling between the piezoresponsive phases. We present here main results of our investigation on the suitability of the high sensitivity MPB piezoelectric perovskite BiScO3–PbTiO3 in combination with ferrimagnetic spinel oxides for magnetoelectric composites. Emphasis has been put on the processing at low temperature to control reactions and interdiffusion between the two oxides. The role of the grain size effects is extensively addressed.

No MeSH data available.


(a) Isothermal magnetization vs magnetic field loops and (b) derivative of square magnetization curves as a function of magnetic field, for trilayers prepared by SPS at different temperatures with the ferrite obtained by wet-chemistry.
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Figure 10: (a) Isothermal magnetization vs magnetic field loops and (b) derivative of square magnetization curves as a function of magnetic field, for trilayers prepared by SPS at different temperatures with the ferrite obtained by wet-chemistry.

Mentions: The magnetization of the trilayers was also measured as a function of the magnetic field. Figure 10(a) shows the RT M–H hysteresis loops for the trilayer prepared at different SPS temperature with the ferrite by wet-chemistry. Similar data was obtained with the ferrite by mechanochemical activation. The saturation magnetization reaches the value of Msat = 51 emu g−1 for the trilayer processed at 1000 °C, very close to that reported for bulk NiFe2O4 [39], and the remnant magnetization Mr and coercive magnetic field Hc were found to be 1.8 emu g−1 and 10 Oe, respectively. These are typical values for this ferrimagnetically ordered material, in which magnetic domain switched under very low applied magnetic field. With decreasing the SPS temperature two effects appear as a consequence of the reduction of the spinel grain size: (i) Msat decreases and the material is increasingly far from reaching saturation of the magnetization, analogous to the results of the P–E curves in the perovskite, and (ii) Mr and Hc continuously increases, indicating that the spin canting contribution to the magnetization starts to dominate. Mr of 3 and 4.1 emu g−1 and Hc of 27 and 70 Oe were found for materials prepared at 900 and 800 °C, respectively. These results are in a good agreement with reports on NiFe2O4 nanocrystalline particles [39].


High-sensitivity piezoelectric perovskites for magnetoelectric composites
(a) Isothermal magnetization vs magnetic field loops and (b) derivative of square magnetization curves as a function of magnetic field, for trilayers prepared by SPS at different temperatures with the ferrite obtained by wet-chemistry.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC5036485&req=5

Figure 10: (a) Isothermal magnetization vs magnetic field loops and (b) derivative of square magnetization curves as a function of magnetic field, for trilayers prepared by SPS at different temperatures with the ferrite obtained by wet-chemistry.
Mentions: The magnetization of the trilayers was also measured as a function of the magnetic field. Figure 10(a) shows the RT M–H hysteresis loops for the trilayer prepared at different SPS temperature with the ferrite by wet-chemistry. Similar data was obtained with the ferrite by mechanochemical activation. The saturation magnetization reaches the value of Msat = 51 emu g−1 for the trilayer processed at 1000 °C, very close to that reported for bulk NiFe2O4 [39], and the remnant magnetization Mr and coercive magnetic field Hc were found to be 1.8 emu g−1 and 10 Oe, respectively. These are typical values for this ferrimagnetically ordered material, in which magnetic domain switched under very low applied magnetic field. With decreasing the SPS temperature two effects appear as a consequence of the reduction of the spinel grain size: (i) Msat decreases and the material is increasingly far from reaching saturation of the magnetization, analogous to the results of the P–E curves in the perovskite, and (ii) Mr and Hc continuously increases, indicating that the spin canting contribution to the magnetization starts to dominate. Mr of 3 and 4.1 emu g−1 and Hc of 27 and 70 Oe were found for materials prepared at 900 and 800 °C, respectively. These results are in a good agreement with reports on NiFe2O4 nanocrystalline particles [39].

View Article: PubMed Central - PubMed

ABSTRACT

A highly topical set of perovskite oxides are high-sensitivity piezoelectric ones, among which Pb(Zr,Ti)O3 at the morphotropic phase boundary (MPB) between ferroelectric rhombohedral and tetragonal polymorphic phases is reckoned a case study. Piezoelectric ceramics are used in a wide range of mature, electromechanical transduction technologies like piezoelectric sensors, actuators and ultrasound generation, to name only a few examples, and more recently for demonstrating novel applications like magnetoelectric composites. In this case, piezoelectric perovskites are combined with magnetostrictive materials to provide magnetoelectricity as a product property of the piezoelectricity and piezomagnetism of the component phases. Interfaces play a key issue, for they control the mechanical coupling between the piezoresponsive phases. We present here main results of our investigation on the suitability of the high sensitivity MPB piezoelectric perovskite BiScO3–PbTiO3 in combination with ferrimagnetic spinel oxides for magnetoelectric composites. Emphasis has been put on the processing at low temperature to control reactions and interdiffusion between the two oxides. The role of the grain size effects is extensively addressed.

No MeSH data available.