Local and electronic structures of BaTiO₃/KNbO₃ nanocomposite particles

In order to enhance the ferroelectric properties, composite nanoparticles with a core-shell structure were prepared, and since the BaTiO 3 (BT) core and KNbO 3 (KN) shell form a hierarchical structure, structural analysis was performed at various scales using a combination of synchrotron radiation and electron microscopy. The KN shell layer was epitaxially grown on the BT core and exhibited a distinct structure from the bulk. Additionally, the local structure and chemical bonding state of the KN shell layer exhibited discrepancies from those of the bulk, a phenomenon attributable to the two-dimensional growth and epitaxial effects analogous to those observed in thin films. There were significant changes in the electronic states not only at the interface with the core, but also at the surface of the composite nanoparticles. Composite nanoparticles can effectively modify the chemical bonding states of ferroelectrics through the effects of dimensionality and size.