Defect Interactions in Sr3La(Fe,Al)(3)O10-delta by Computer Simulations and Mossbauer Spectroscopy

abstract

Moderate Al3+ doping in Ruddlesden-Popper type Sr3LaFe3O10-delta leads to complete reconfiguration of the electronic sublattice. While oxygen vacancies, Fe4+, and substitutional cations all exhibit energetic affinity for the equatorial perovskite-like planes, the atomistic computer simulations showed that Coulombic repulsion between the point defects and local lattice deformations near Al3+ result in hole displacement out of these layers when the content of vacant anion sites and/or aluminum is significant. The Al3+ cations tend to form relatively stable aluminum-oxygen tetrahedra, which are energetically favorable for the central perovskite layers and distort neighboring polyhedra formed by iron These effects and partial hole localization in the apical iron-oxygen polyhedra adjacent to Al3+ were confirmed by Mossbauer Spectroscopy analysis of Sr3LaFe3-xAlxO10-delta (x = 0.3-0.6, delta = 0-1).

keywords

MIXED CONDUCTIVITY; CHARGE DISPROPORTIONATION; OXYGEN NONSTOICHIOMETRY; ELECTRICAL-PROPERTIES; ELECTRODE MATERIALS; SPECTRA; TRANSPORT; OXIDES; BROWNMILLERITE; MICRODOMAINS

subject category

Chemistry; Materials Science

authors

Tsipis, EV; Naumovich, EN; Patrakeev, MV; Anikina, PV; Waerenborgh, JC; Kharton, VV

our authors

Groups

acknowledgements

This work was partially supported by FCT, Portugal (Projects PTDC/CTNI/64357/2006 and SFRH/BPD/28629/2006)

Share this project:

Related Publications

We use cookies for marketing activities and to offer you a better experience. By clicking “Accept Cookies” you agree with our cookie policy. Read about how we use cookies by clicking "Privacy and Cookie Policy".