Synthesis of Strontium Titanate Nanoparticles by Ultrasonic Irradiation

The SrTiO3 is a ceramic with thermoelectric properties, i.e., it can generate electrical voltage between its terminals when subjected to a temperature gradient, and this behavior is known as Seebeck effect. One parameter for quantifying the efficiency of converting thermal energy into electric energy is through the value of the Figure of Merit (ZT). STO nanostructured powders were synthesized by ultrasonic irradiation (USS), and the effects of USS in STO synthesis were evaluate, and it was compared with the conventional route of solid-state reaction (SSR). USS powders were produced by solubilization of Ti(C4H9O)(4) and SrCO3 in acid solution and following the posterior precipitation by adding NH4OH solution. After drying process, the precipitated was added to a KOH solution and was subjected to ultrasonic irradiation to promote the STO formation. DRX analysis revealed that from USS method it was possible to obtain exclusive STO phase. SEM characterization showed that the USS powder presented particle size about 100nm, which was much lower than that obtained by SSR, about 250nm.