Influence of reactant type on the Sr incorporation grade and structural characteristics of Ba1−xSrxTiO3 (x=0−1) grown by sol-gel-hydrothermal synthesis

The influence of barium and strontium starting reactants used in different mole ratios, BaCl2 and Ba(OH)2, SrCl2 and Sr(OH)2, on the chemical and structural properties of Ba1−xSrxTiO3 (x=0−1) (BST) nanoparticles prepared via sol-gel-hydrothermal synthesis in an oxygen atmosphere is discussed. The effect of the type of reactant on the relative amount of Sr incorporated in BST compound was also analysed. The synthesised BST nanoparticles showed differences in their structural and chemical characteristics, which were attributed to the presence of Cl− or OH− anions during the synthesis of the compound. The structure, morphology and oxidation state of the samples were studied by X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy, respectively. In addition, theoretical calculations using cluster models were carried out to understand the possible phases formed of BST, the effect of the Sr incorporation and the possible presence of oxygen vacancies inside the BST structure.