Perovskite phase formation, phase transformations and electrical properties of lead-nickel niobate - Lead zirconate ceramics

Abstract

The perovskite structure of lead zirconatelead nickel niobate ceramics, (1-x)PbZrO3-xPb(Ni1/3Nb2/3)O3 (PZ - PNN) with x = 0.0-0.5, were synthesized via the columbite precursor method. The formation of the perovskite phase in the calcined powders has been investigated as a function of calcination conditions by TG-DTA and XRD techniques. The complete solid solutions of perovskite phase of PZ-PNN ceramics were obtained over a wide compositional range. The results showed that the concentration of the PNN phase increased the calcination temperature must be increased in order to obtain phase-pure perovskite. In addition, x-ray diffraction indicated a phase transformation from a orthorhombic to a pseudo-cubic phase when the fraction of PNN was increased. A higher relative permittivity value, as a consequence of the higher PNN concentration, was observed.