Characterization of (Fe'Zr,Ti - VO..). defect dipoles in (La,Fe)-codoped PZT 52.5/47.5 piezoelectric ceramics by multifrequency electron paramagnetic resonance spectroscopy.
Ferroelectric 1 mol.% La(3)+ and 0.5 mol.% Fe(3)+ codoped Pb[Zr0(0.54)Ti0(0.46)]O(3) ceramics were studied by means of multifrequency electron paramagnetic resonance (EPR) spectroscopy. The obtained results prove that iron is incorporated at the [Zr,Ti]-site, acting as an acceptor and building a charged Fe'(Zr,Ti) - V(O)..)(.) defect dipole with a directly coordinated oxygen vacancy for partial charge compensation. This feature of the defect associates has hitherto been identified only in hard, exclusively Fe(3)+-doped PZT compounds. The present results show, however, that a similar defect association of the Fe3+ functional center with a V(O)..) also exists in soft, donor-acceptor (La(3)+,Fe(3)+)-codoped PZT. According to models developed by Arlt et al. electric dipoles from defect associates, such as the Fe'(Zr,Ti) - V(O)..)(.) defect associate, which may give rise to an internal bias field that is discussed being responsible for ferroelectric aging.
Eduard-Zintl-Institute, Darmstadt University of Technology, D-64287 Darmstadt, Germany.
Emre
E
Erdem
Rüdiger-A
RA
Eichel
H
H
Kungl
M J
MJ
Hoffmann
A
A
Ozarowski
J
J
Van Tol
L C
LC
Brunel
D002516:Ceramics / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D004553:Electric Conductivity; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D007854:Lead / Q000737:chemistry*; D008422:Materials Testing; D008567:Membranes, Artificial; D014025:Titanium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry*
D008567:Membranes, Artificial; C065536:lead titanate zirconate; D007854:Lead; D015040:Zirconium; D014025:Titanium