PbMg1/3Nb2/3O3-doping effects on structural, thermal, Raman, dielectric and ferroelectric properties of BaTiO3 ceramics

Low-lead content (1 − x)BT-xPMN (x = 0, 0.025, 0.05, 0.075, 0.10 and 0.15) ceramics were prepared by a two-step conventional mixed-oxide method. The crystal structure, phase transitions behavior, thermal, Raman and electrical properties of these ceramics were investigated for the first time. The compositions show formation of perovskite-type solid solutions and undergo a sequence of phase transitions characteristic of pure BT (except for samples with x = 0.075 and x = 0.10 in which a direct tetragonal-rhombohedral phase transition, and x = 0.15 in which only cubic-rhombohedral phase transition, was observed). Dielectric studies revealed that, with a rise of PMN content, the dielectric behaviors of the obtained ceramics changed from that of normal ferroelectrics to relaxor-like ones. The transition temperatures and the maximum electric permittivity decrease with increasing PMN content in the system. In general, the transition temperatures observed by means of dielectric studies are in good agreement with those obtained from XRD and DSC measurements. The possible origin of the observed effects was discussed. We suggest that the presented materials can be a good starting point for the development of new low-lead electronic ceramics.