Abstract:
Multiferroic materials are of considerable interest due to the intriguing science and application potential. Effects of Pb(Zr0.52Ti0.48)O-3 (PZT) modification on the structural, electrical, ferroelectric domain structure and ferromagnetic properties of BiFeO3 (BFO) polycrystalline films were investigated in detail. A morphotropic phase boundaries between rhombohedral perovskite (R3c) and tetragonal (P4 mm) were found in the PZT modified BFO thin films. 2% and 5% PZT modified BFO films exhibit uniform surface, larger domain size, fewer domain walls density, and lower electrical conductivity comparing with the pure BFO film. The 2% and 5% PZT modified BFO thin films show well saturated P-E hysteresis loops with improved remnant polarization close to 76.8 and 96.7 mu C/cm(2). The improved ferroelectric and dielectric properties of the PZT modified BFO films are attributed to the modified phase structure and bond lengths of Bi-O, decreased concentration of defects and defect dipole complexes, and different domain structures. The saturated magnetizations under a magnetic field of 5 000 Oe at room temperature are 8.5, 11.4, and 14.3 emu/cm(3) for the pure, 2% and 5% PZT modified BFO films, respectively. The elevated magnetic properties of PZT modified BFO may be due to the distorted spin cycloid, varied canting angle of Fe-O-Fe bond via the Zr/Ti substitution, and suppressed spiral spin structure via Pb ions substitution of Bi ions. (C) 2011 American Institute of Physics. [doi:10.1063/1.3668123]
