A surfactant-free route to synthesize Ba x Sr1−x TiO3 nanoparticles at room temperature, their dielectric and microwave absorption properties

Perovskite materials, such as Ba x Sr1−x TiO3 (BST), have been continuously receiving attentions due to their unique ferroelectric, pyroelectric, dielectric, piezoelectric and electric-optic properties. Here, we report a facile route for the synthesis of BST nanocrystalline materials by fast mixing of MCl2 (M = Ba, Sr) aqueous solution and titanium isopropoxide ethanol solution at room temperature without using any surfactants or structure-directing templates. The molar ratio of Ba/Sr was controlled by adjusting the original molar ratio of BaCl2·2H2O and SrCl2·6H2O. The dielectric properties and microwave absorption capability of the BST nanocrystalline were studied. The results indicate that the BST nanocrystalline material has the best dielectric and microwave absorption properties in the case of Ba0.7Sr0.3TiO3. The present strategy is facile, low cost and high yield, which may provide a new route for the synthesis of other perovskite materials.