Effect of Zr/Ti ratio on structural, vibrational, magnetic and dielectric properties of (0.95)PbZrxTi1-xO3-(0.05)BiFeO3 ceramics

Abstract

We have investigated the structural, vibrational, ferroelectric, magnetic and dielectric properties of (0.95)PbZrxTi1-xO3-(0.05)BiFeO3 (x = 0.51, 0.53 and 0.55) ceramics, prepared by the sol-gel route. Rietveld refined X-ray powder diffraction patterns of these samples confirm the single phase formation with a tetragonal structure (P4mm) symmetry at room temperature. The Williamson-Hall analysis was used to study the contributions of crystallite size and lattice strain on the peak broadening in the different patterns. Reduction in c/a ratio with x indicates poor ferroelectric behaviour for x = 0.55. Infrared spectroscopy revealed the slight shift of phonon modes towards the lower wave number side and increase in the bond length with increasing x which is in good agreement with the Rietveld analysis. Room temperature dielectric measurements of these samples show dispersion in epsilon(r) which is associated with a peak in tan delta versus logf plots. M-H hysteresis loops exhibit weak ferromagnetism for x = 0.51 and almost anti-ferromagnetic behaviour for x = 0.55