Structural Evolution and Enhanced Energy Density, Ferroelectric Property Investigation in Gd Substituted NBT – BT Lead Free Ferroelectric Ceramics

¹Department of Engineering Physics, A.U. College of Engineering (A), Andhra University, Visakhapatnam, Andhra Pradesh 530003, India

²Defence Metallurgical Research Laboratory, Hyderabad 500058, India

³Rajiv Gandhi University of Knowledge Technologies, IIIT – Idupulapaya, Kadapa, Andhra Pradesh, India

Adv. Mater. Lett., 2021, 12 (4), 21041622

DOI: 10.5185/amlett.2021.041622

Publication Date (Web): Feb 01, 2021

Copyright © IAAM-VBRI Press

E-mail: p.thirupathi@rguktrkv.ac.in

Abstract

Gd substituted 0.94(Na0.5Bi0.5-xGdxTiO3) – 0.06 BaTiO3 (x = 0.00, 0.01, 0.02 and 0.03) lead free ferroelectric ceramics were synthesized by a conventional solid-state synthesis. Room temperature XRD reveals the formation of perovskite structure without secondary impurity peaks. Rietveld refinement pattern confirms the coexistence of dual phase i.e., major monoclinic (Cc) and minor tetragonal (P4mm). More tetragonality and slim ferroelectric properties were noted with increasing Gd content in NBT-BT solid solutions. A collective Gd substitution stimulates the transition of PE loop shape from square to slim with slanted leads to suit for high energy density storage applications. The optimum energy storage properties can be achieved for x = 0.03 ceramic showed a recoverable energy density 1.59 J/cm3 and a remarkably best energy efficiency of 67% under 65 kV/cm at room temperature.

Keywords

Lead free, sodium bismuth titanate (Na_0.5Bi_0.5TiO₃), energy storage density