The electrical performance of ceramics materials with perovskite structure doped with metallic ions

摘要

The ceramics materials with ABO(3) structure based on iron or silver doped sodium tantalate, were successfully synthesized using the ultrasonically method with immersed sonotrode in the reaction medium followed by heat treatment at 600 degrees C. Samples were doped with silver for the A site of the perovskite lattice and with iron for the B site. The doping was performed in order to improve the electrical properties through change the crystalline structure and prevent ordering of the oxygen vacancies in these materials. The obtained materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX) and electrical measurements. Structural analysis shows that the obtained materials have cubic structure and a homogeneous composition, without secondary compounds. Electrical measurements indicate that the presence of metal ions of iron or silver in the structure of NaTaO3 lead to decreases of the gap band energy, resulting in increase of electric conductivity.