Sr vacancy segregation by heat treatment at SrTiO3 grain boundary

Abstract

Electron energy loss near-edge structures (ELNES) and first-principles band structure calculations were combined in order to identify native defects which are segregated by heat treatments at the vicinity of SrTiO3 grain boundary (GB). Spectral differences between the bulk and the vicinity of GB mainly appear around the second peak of OK ELNES. The spectral differences can be reproduced by calculating the theoretical OK ELNES from the first-nearest-neighbor oxygen to a Sr vacancy. It is therefore concluded that the Sr vacancies are concentrated in the vicinity of GB by the heat treatment.