Hydrothermal Formation and Growth of Single- and Double-Layer BaTiO3 and SrTiO3 Films on the Flexible Polymer Film Substrates from Sol−Gel Amorphous Titanium Oxide Films

Polycrystalline single- and double-layer BaTiO 3 (BT) and SrTiO 3 (ST) films on flexible polymer films were synthesized by hydrothermal treatments of sol−gel amorphous titanium oxide films with M(OH) 2 (M = Ba, Sr) aqueous solutions from 60 to 150 °C. The amorphous titanium oxide films were prepared by a dip-coating method from a sol−gel precursor. The structure of the films formed under a variety of conditions characterized by X-ray diffraction (XRD) revealed that the polycrystalline cubic MTiO 3 (M = Ba, Sr) films were formed. The surface morphology of the films observed by scanning electron microscopy (SEM) indicated that the films were uniform. A model for the formation and growth of MTiO 3 films from amorphous titanium oxide films under hydrothermal conditions was proposed.