Artículos de revistas
Experimental evidence of enhanced ferroelectricity in Ca doped BiFeO3
Date
2014-04-15Registration in:
Materials Chemistry And Physics. Lausanne: Elsevier Science Sa, v. 144, n. 3, p. 476-483, 2014.
0254-0584
10.1016/j.matchemphys.2014.01.022
WOS:000333493400037
1922357184842767
0000-0003-1300-4978
Author
Universidade Estadual Paulista (Unesp)
Institutions
Abstract
Calcium (Ca)-doped bismuth ferrite (BiFeO3) thin films prepared by using the polymeric precursor method (PPM) were characterized by X-ray diffraction (XRD), field emission gun scanning electron microscopy (FEG-SEM), transmission electron microscopy (TEM), polarization and piezoelectric measurements. Structural studies by XRD and TEM reveal the co-existence of distorted rhombohedral and tetragonal phases in the highest doped BiFeO3 where enhanced ferroelectric and piezoelectric properties are produced by internal strain. Resistive switching is observed in BFO and Ca-doped BFO which are affected by the barrier contact and work function of multiferroic materials and Pt electrodes. A high coercive field in the hysteresis loop is observed for the BiFeO3 film. Piezoelectric properties are improved in the highest Ca-doped sample due to changes in the crystal structure of BFO for a primitive cubic perovskite lattice with four-fold symmetry and a large tetragonal distortion within the crystal domain. This observation introduces magnetoelectronics at room temperature by combining electronic conduction with electric and magnetic degrees of freedom which are already present in the multiferroic BiFeO3. (C) 2014 Elsevier B.V. All rights reserved.