Synthesis of SrTiO3 from celestite and rutile by mechanical activation assisted Solid-State reaction

This study introduced a novel synthesis of SrTiO₃ employing the mechanical activation-assisted solid-state reaction of SrSO₄ and TiO₂. The synthesis process was monitored through thermogravimetric analysis (TGA), X-Ray Diffraction (XRD), and field emission scanning electron microscope (SEM). The mechanical activation caused an intense distortion to the crystal structure of SrSO₄ and TiO₂, enhancing their chemical reactivities. As a result, SrTiO₃ could be synthesized from a mechanically activated SrSO₄-TiO₂ mixture after thermal treatment at 1000 °C in an inert atmosphere that was not possible for the non-activated mixture. The formation of strontium titanate was retarded and slowed down in the air under the same conditions. The maximum yield of SrTiO₃ (about 97%₎ was obtained after milling for 10 h, followed by solid-state treatment at 1000 °C for 2 h under argon atmosphere. XRD analysis showed that the produced SrTiO₃ had a mean crystallite size of 70 nm. SEM investigation indicated the formation of cubic-like particles of less than 100 nm particle size. Also, Energy Dispersive X-Ray Spectroscopy (EDS) analysis confirmed that the atomic percentage of Sr, Ti, and O in the product was typically matched with the SrTiO₃ chemical formula.