Low-temperature synthesis and analysis of barium titanate nanoparticles with excess barium

BaTiO3 nanoparticles with excess barium are directly synthesized from solution at 65 °C. It is noted that a small amount of BaCO3 exists in the as-prepared samples. A series of standard mixtures with different proportion of BaTiO3 and BaCO3 are measured by XRD analysis to quantify the amount of BaCO3 in our synthesized samples. After a deduction of the amount of BaCO3, the concentration of excess barium in the lattice of BaTiO3 nanoparticles can be determined and the results show that the excess barium can reach a considerable concentration. The influences of defects and surfaces on BaTiO3 nanoparticles with excess barium are analyzed and two important reasons for the high concentration are also given.