Influence Of Gd On Structural And Impedance Properties Of Multiferroic Composites: BiFeO3-PbTiO3

Materials Research Laboratory, School of Physics, Sambalpur University, JyotiVihar, Burla 768019, Odisha, India

Adv. Mater. Lett., 2015, 6 (11), pp 947-953

DOI: 10.5185/amlett.2015.5839

Publication Date (Web): Oct 26, 2015

Copyright © IAAM-VBRI Press

E-mail: banarjibehera@gmail.com

Abstract

The Gd-modified BiFeO₃-PbTiO₃ composites i.e. 0.5BiGd_xFe_1-xO₃-0.5PbTiO₃ (BG_xF_1-x-PT) with x=0.00, 0.05, 0.10, 0.15, 0.20, were prepared by mixed oxide method at high temperature. The structural study reveals that the composites showed tetragonal crystal structure at room temperature and tetragonality (c/a ratio) of composites decrease with increase in Gd concentration. The average crystallite size of the composites was found to be in the range of 30-89 nm. Surface morphology of the composites was studied by scanning electron microscopy (SEM). The Goldschmidt tolerance factors of the composites were found to be in the range of 0.989-0.976. The nature of Nyquist plot confirmed the presence of both bulk and grain boundary effects, and non-Debye type of relaxation process occur in the composites. The activation energy of the composites was found to be in the range 0.13-1.38eV. The analyses of ac conductivity data obey the universal agreement with Jonscher’s power law. Further, the explanation of conduction mechanism through correlated barrier hopping (CBH) model was discussed.

Keywords

Ceramics, X-ray diffraction, complex impedance, electrical properties.