Low-temperature synthesis of Nb-doped and Mn-doped SrTiO3 with easily controllable particle size

Heterovalently doped perovskite-type oxides are used in various electronic applications. Herein, we propose a low-temperature synthesis method for Nb- and Mn-doped SrTiO3 particles with a wide range of particle sizes that is conducted at temperatures close to room temperature (RT). The cation-doped SrTiO3 particles were synthesized under diverse solution conditions by varying the aging temperature, aging period, viscosity of solvents, and OH- concentration using facile and low-cost methods. The particle sizes were simply controlled by changing the ratio of H2O/ethanol solvents owing to their difference in viscosity at low temperatures. The uniformity of the particle sizes was significantly improved via a two-step aging process, that is, heating at a low temperature followed by RT aging. Additionally, the OH- concentration in aqueous solution had considerable impact on the rate of crystal growth, affecting particle size as well as morphology. This study demonstrates the feasibility for the low-temperature synthesis of cation-doped perovskite-type materials.