TY  - JOUR
AU  - Du, Hongchu
AU  - Jia, Chun-Lin
AU  - Houben, Lothar
AU  - Metlenko, Veronika
AU  - De Souza, Roger A.
AU  - Waser, R.
AU  - Mayer, Joachim
TI  - Atomic structure and chemistry of dislocation cores at low-angle tilt grain boundary in SrTiO3 bicrystals
JO  - Acta materialia
VL  - 89
SN  - 1359-6454
CY  - Amsterdam [u.a.]
PB  - Elsevier Science
M1  - FZJ-2015-01616
SP  - 344 - 351
PY  - 2015
AB  - Dislocations in perovskite oxides have been found to have important impacts on their electronic and ionic transportation properties, which are believed to be related to the structure and chemistry of dislocation cores. For dislocation cores at a 6° low-angle [0 0 1] tilt grain boundary in SrTiO3, an embedded TiOx rocksalt-like structure has been suggested, consistent with a deficiency of Sr. However, direct evidence supporting these suggestions has not been obtained up to now. In this work, we reveal the atomic structure and chemistry of edge dislocation cores at a low-angle [0 0 1] symmetric tilt-boundary in SrTiO3 bicrystals by imaging techniques of high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and electron energy loss spectroscopy (EELS) with an FEI Titan cube3 60–300 (PICO) microscope operated at 80 kV. The experimental results demonstrate direct evidence for a local coordination of edge-sharing TiO6 octahedra at the dislocation cores, which can be understood as the result of strain. The local coordination of edge-sharing TiO6 octahedra is associated with the face-centered cubic (FCC) NaCl-type TiO phase. The present study therefore provides a solid structural and chemical basis for understanding the properties of dislocations.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000353249100033
DO  - DOI:10.1016/j.actamat.2015.02.016
UR  - https://juser.fz-juelich.de/record/188155
ER  -