Hydrothermal synthesis of monosized Bi0.5Na0.5TiO3 spherical particles under low alkaline solution concentration

Monosized spherical particles of bismuth sodium titanate (Bi0.5Na0.5TiO3, abbreviated as BNT) have been successfully synthesized by a hydrothermal synthesis method in a range of 0.01–3 M alkaline solutions using bismuth nitrate (Bi(NO3)3·5H2O), sodium hydroxide (NaOH), and tetrabutyl titanate (Ti(OC4H9)4) as the bismuth, sodium, and titanium source, respectively. The as-prepared BNT particles were characterized by employing techniques including X-ray powder diffraction (XRD), scanning electron microscope (SEM), energy dispersive analysis of X-rays (EDS), and high-resolution transmission electron microscope (HRTEM). The effects of reactant concentrations and Ti/Bi molar ratio on the precipitation of BNT particles were briefly investigated. It indicated that for the formation of BNT spherical particles in aqueous solution system, the ratio of Ti to Bi should be kept at Ti/Bi < 2 and the prepared particles have a monosized spherical morphology, and the particle size ranges from micron (∼2 μm) to submicron (200–500 nm) with adjusting the reactant concentration. Furthermore, increasing the ratio of Ti to Bi (Ti/Bi = 2) can promote synthesis of BNT nano-wires.