Structural and morphological transformations of BaTiO3 nanocrystals in thin layers of borate oxide glasses

Abstract

The influence of thin layers (2–15 μm) of some oxide glass melts on BaTiO3 nanocrystallites has been investigated using X-ray diffractometry and scanning electron microscopy. It has been shown that lead borate and sodium borate glass melts bring about the dissolution of BaTiO3 nanocrystallites and the subsequent crystallization in glasses of lead titanate PbTiO3 and sodium titanate Na2TiO3, respectively. It has been found that thin layers of melts of these glasses have a strong orientation effect on crystallites of the PbTiO3 and Na2TiO3 compounds newly synthesized from barium titanate. The orientation effect exerted by these glass layers results in the formation of a pronounced texture of the perovskite crystallites with the texture axes oriented along the [100] and [001] directions parallel to the surface normal of the substrate for lead titanate and the orientation of the \((21\bar 1)\) planes of the film surface for the sodium titanium oxide.