Modified structure and optical properties of multiferroic Pb(Zr0.53Ti0.47)(x)(Fe0.5Nb0.5)((1-x))O-3 ceramics

摘要

The Pb(Zr0.53Ti0.47)(x)(Fe0.5Nb0.5)((1-x))O-3 (xPZTFN) multiferroic ceramics synthesized by a solid state reaction method have been investigated by means of structural characterizations and optical measurement. All the samples show polycrystalline perovskite structures with dense microstructures, but exhibit a gradual transition behavior from cubic to tetragonal structure with increasing x. The xPZTFN (0 <= x <= 0.2) ceramics have an average crystal structure described as the centrosymmetric cubic perovskite, whereas x >= 0.4 ceramics are consistent with a non-centrosymmetric tetragonal structure. Coexistence of both cubic and tetragonal symmetries is observed for x=0.3. Raman spectroscopy analysis corroborates the change in average structure with the x but also show the local crystal symmetry for 0 < x < 0.2 ceramics to deviate from the idealized cubic perovskite. Optical absorption spectra indicate that Pb(Zr0.53Ti0.47)O-3 (PZT) doping has an effect on the energy band structure. The band gap (E-g) of xPZTFN (0 <= x <= 0.7) ceramics is in the range of 2.08-2.33 eV, much smaller than the 3.21 eV E-g of the PZT material. This result shows that the modification of optical property can be achieved by manipulating the composition in xPZTFN materials. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.