Solvothermal synthesis of BaTiO₃ nanoparticles from K₂Ti₆O₁₃ precursors

BaTiO₃ nanoparticles were prepared for the first time employing a solvothermal process from the synthetic precursors of K₂Ti₆O₁₃ nano-whiskers. The obtained samples were characterized by X-ray diffraction, transmission electron microscopy, selected area electron diffraction, and high-resolution transmission electron microscopy, etc. The results indicate that well-crystallized single-phase BaTiO₃ nanoparticles are synthesized using K₂Ti₆O₁₃ as precursors under solvothermal conditions at as low as 0.9 M. The solvothermal method facilitates the crystallinity and formation of the BaTiO₃ nanoparticles. However, the K⁺ ions cannot be completely replaced by Ba²⁺ by the hydrothermal method even at 10 M due to its unique and extremely stable "tunnel" structure. The solvothermal method provides new avenues for the ion-exchange synthesis of a variety of other perovskite-type materials such as MTiO₃ (M = Pb, Sr, Ca, etc.).