Formation mechanisms of SrTiO3 nanoparticles under hydrothermal conditions

Formation mechanisms of SrTiO3 particles from TiO2·nH2O gel under hydrothermal condition have been investigated. It was found that the mechanisms conformed to a new model, i.e. dissolution–crystallization–aggregative growth–recrystallization mechanism model. The dissolution of TiO2·nH2O gel was a slow process and controlled the whole reaction. The crystallinity of TiO2·nH2O gel was an important factor, influencing the solubility of TiO2·nH2O gel, the formation mechanism of the SrTiO3 nucleus, and the stability of the primary particles of aggregative growth. The particle size of hydrothermally synthesized SrTiO3 could also be controlled by modifying the crystallinity of the TiO2·nH2O gel; under certain condition, nanoparticles of SrTiO3 could be synthesized hydrothermally.