Excess titanium in barium titanate nanoparticles directly synthesized from solution

The formation mechanism of excess titanium in BaTiO3 nanoparticles is different from that in BaTiO3 bulk materials. In this study, we analyzed the concentration of excess titanium in BaTiO3 nanoparticles, which were directly synthesized from solution at 65 °C and it was found that it can reach an abnormal high concentration and keep the normal perovskite structure. The mechanism is discussed from the points of both defect chemistry and surface effect. The dielectric property of the ceramics fabricated from as-prepared nanoparticles with different concentration of excess titanium is also studied.