Investigation on electromechanical properties of A-site donor rare-earth modified tetragonal (4Â mm) lead barium niobate (PBN55) ceramics

In this paper, Pb0.55−(3y/2)CeyBa0.45Nb2O6 ceramics with tetragonal tungsten-bronze structure prepared through the solid-state reaction method and characterized for phase formation, density, dielectric and piezoelectric properties are reported. The XRD analysis showed the presence of a tetragonal tungsten-bronze structure, which intensified with increasing Ce content. The stability of the tetragonal tungsten-bronze phase has been discussed with the electronegativity difference and the tolerance factor. The Curie temperature (Tc) systematically lowered when Ce was incorporated into tetragonal PBN lattice. The room-temperature dielectric constant (εRT) of Ce-modified lead barium niobate (PBN) compositions has enhanced from C0 to C3 and thereafter decreased. The influence of Ce on piezoelectric properties of tetragonal PBN system has been evaluated. The piezoelectric coefficients (d, g, k and Qm) were characterized. The C3 composition exhibited optimum piezoelectric properties in the series, and this composition could be suitable for piezoelectric applications.