Identification of Local Phase of Nanoscale BaTiO3 Powders by High-Resolution Electron Energy Loss Spectroscopy

Abstract

AbstractThe electron energy loss spectroscopy (EELS) technique was applied to investigate the local variation in the phase of barium titanate (BaTiO3) ceramics. It was found that the fine structure of the titanium L2,3 edge and their satellite peaks were sensitively varied with the tetragonal–cubic phase transition. The peak splitting of Ti-L3 edge of tetragonal-phased BaTiO3 ceramics was widened because of the increased crystal field effect compared with that of cubic-phased BaTiO3. In case of nanoscale BaTiO3 powders, the L3 edge splitting of the core region was found to be smaller than that of the shell region. The energy gap between peaks t2g and eg varied from 2.36 to 1.94 eV with changing the probe position from 1 to 20 nm from the surface. These results suggest that the EELS technique can be used to identify the local phase of sintered BaTiO3 ceramics.