Solution synthesis and growth mechanism of SrTiO₃ mesocrystals

Single-crystalline SrTiO₃ mesocrystals were synthesized via sol-precipitation coupled with a hydrothermal process using oleic acid as a capping agent. To clarify the growth mechanism, the time-dependence morphology, size, and growth process of SrTiO₃ mesocrystal were investigated. SrTiO₃ mesocrystals formed from oriented aggregates of Sr-Ti-O nanorods, which were subsequently transformed into irregular morphologies via the formation of the SrTiO₃ phase. Then oriented fusion of the irregular particles gave a mesocrystal structure. The addition of oleic acid accelerated the formation of Sr-Ti-O nanorods, oriented the fusion of irregular SrTiO₃ particles, and formed the cubic morphology of SrTiO ₃ mesocrystals.