This title appears in the Scientific Report : 2014 

Defect-Structure - Property Relationships in aliovalently doped and non-stoichiometric Perovskite Oxides
Eichel, Rüdiger-A. (Corresponding Author)
Grundlagen der Elektrochemie; IEK-9
2014
2014
International Symposium on Advanced Functional Materials, Kuala Lumpur (Malaysia), 2014-08-01 - 2014-08-02
Conference Presentation
Renewable Energies
Ferroelectric materials based on perovskite oxides offer the advantage that materials properties may be systematically tailored over a wide range either by controlling the microstructre in terms of processing or by means of aliovalent doping and defined non-stoichiometry [1]. Although the strategy of introducing atomic-scale defects that may form defect complexes, which in turn impact the mobility of ferroelectric domain walls, is valid not only for Pb[Zr,Ti]O3 (PZT), but also for lead-free alternatives [2] such as [Bi,Na]TiO3 (BNT) or [K,Na]NbO3 (KNN) for instance, the corresponding defect structure when using Fe2O3- or CuO-doping significantly differs from PZT with tetravalent B-site to KNN where the B-site is pentavalent.Focusing on 'hard' ferroelectrics, the energetics for the formation of dimeric [3,4] and trimeric [5,6] defect complexes between acceptor-type dopant ions and charge compensating oxygen vacancies is considered both from an experimental and theoretical perspective. Moreover, the position of these defects with respect to domain walls [7], their interaction with 180° and non-180° domain walls [5], as well as the reorientation of the defect dipoles during poling [8] is discussed.references:[1] R.-A. Eichel, H. Kungl and P. Jakes, Mat. Tech. 28 (2013) 5 241[2] R.-A. Eichel, H. Kungl, Funct. Mat. Lett. 3 (2010) 1–4[3] R.-A. Eichel, P. Erhart, P. Träskelin, K. Albe, H. Kungl and M.J. Hoffmann, Phys. Rev. Lett. 100 (2008) 095504[4] E. Aksel, E. Erdem, P. Jakes, J.L. Jones and R.-A. Eichel, Appl. Phys. Lett. 97 (2010) 012903[5] R.-A. Eichel, E. Erünal, P. Jakes, S. Körbel, C. Elsässer, H. Kungl, J. Acker and M.J. Hoffmann, Appl. Phys. Lett. 102 (2013) 242908[6] E. Erünal, P. Jakes, S. Körbel, J. Acker, H. Kungl, C. Elsässer, M.J. Hoffmann and R.-A. Eichel, Phys. Rev. B 84, (2011) 184113[7] P. Jakes, E. Erdem, R.-A. Eichel, L. Jin and D. Damjanovic, Appl. Phys. Lett. 98 (2011) 072907[8] L.X. Zhang, E. Erdem, X. Ren and R.-A. Eichel, Appl. Phys. Lett. 93 (2008) 202901