Publication
Title
Nanoscale ordering in oxygen deficient quintuple perovskite $Sm_{2-\epsilon}Ba_{3+\epsilon}Fe_{5}O_{15-\delta}$ : implication for magnetism and oxygen stoichiometry
Author
Abstract
 The investigation of the system SmBaFe-O in air has allowed an oxygen deficient perovskite Sm2-epsilon Ba3+epsilon Fe5O15-delta (delta = 0.75, epsilon = 0.125) to be synthesized. In contrast to the XRPD pattern which gives a cubic symmetry (a(p) = 3.934 angstrom), the combined HREM/EELS study shows that this phase is nanoscale ordered with a quintuple tetragonal cell, a(p) X a(p) X 5(ap). The nanodomains exhibit a unique stacking sequence of the A-site cationic layers along the crystallographic c-axis, namely SmBaBa/SmBa/SmBaSm, and are chemically twinned in the three crystallographic directions. The nanoscale ordering of this perovskite explains its peculiar magnetic properties on the basis of antiferromagnetic interactions with spin blockade at the boundary between the nanodomains. The variation of electrical conductivity and oxygen content of this oxide versus temperature suggest potential SOFC applications. They may be related to the particular distribution of oxygen vacancies in the lattice and to the 3d(5)(L) under bar configuration of iron.
Language
English
Source (journal)
Chemistry of materials. - Washington, D.C, 1989, currens
Publication
Washington, D.C : American Chemical Society, 2014
ISSN
0897-4756
Volume/pages
26:21(2014), p. 6303-6310
ISI
000344905600029
Full text (Publisher's DOI)
UAntwerpen
 Faculty/Department Research group [E?say:metaLocaldata.cgzprojectinf] Counting Atoms in Nanomaterials (COUNTATOMS).Revealing the source of emergent properties in complex oxides via direct imaging of charge/orbital/spin ordering.Exploring electron vortex beams (VORTEX). Publication type Subject Affiliation Publications with a UAntwerp address