Erdem Emre, Eichel Rüdiger-A, Kungl H, Hoffmann M J, Ozarowski A, Van Tol J, Brunel L C
Eduard-Zintl-Institute, Darmstadt University of Technology, D-64287 Darmstadt, Germany.
IEEE Trans Ultrason Ferroelectr Freq Control. 2008 May;55(5):1061-8. doi: 10.1109/TUFFC.2008.757.
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.
通过多频电子顺磁共振（EPR）光谱研究了铁电体1摩尔％La(3+)和0.5摩尔％Fe(3+)共掺杂的Pb[Zr0(0.54)Ti0(0.46)]O(3)陶瓷。所得结果证明铁掺入[Zr,Ti]位点，作为受主并形成带电荷的Fe'(Zr,Ti)-V(O)..)(.)缺陷偶极子，其具有直接配位的氧空位用于部分电荷补偿。缺陷缔合体的这一特征迄今仅在硬的、仅Fe(3+)掺杂的PZT化合物中被识别。然而，目前的结果表明，在软的、施主-受主（La(3)+,Fe(3)+）共掺杂的PZT中也存在Fe3+功能中心与V(O)..)的类似缺陷缔合。根据Arlt等人开发的模型，来自缺陷缔合体的电偶极子，如Fe'(Zr,Ti)-V(O)..)(.)缺陷缔合体，可能产生一个内部偏置场，该偏置场被认为是铁电老化的原因。
