Correlative chemical and structural nanocharacterization of a pseudo?binary 0.75Bi(Fe _0.97 Ti _0.03 )O ₃ ?0.25BaTiO ₃ ceramic

Fast cooling after sintering or annealing of BiFeO3-BaTiO3 mixed-oxide ceramics yields core-shell structures that give excellent functional properties, but their precise phase assemblage and nanostructure remains an open question. By comparing conventional electron energy loss spectroscopy (EELS) with scanning precession diffraction (SPED) mapping using a direct detector, we correlate chemical composition the presence absence octahedral tilting changes in lattice parameters. This reveals some grains have three-phase BaTiO3-rich pseudocubic shell; BiFeO3-rich outer core consistent R3c structure; inner richer Ba even poorer Ti, which seems to show structure slightly smaller parameter than shell region. last has not been previously identified these materials, fit previous studies. These cores are likely be non-polar play no part ferroelectric properties. Nevertheless, combination EELS SPED clearly provides novel way examine heterogeneous microstructures high spatial resolution, thus revealing phases may too subtle detect more techniques.