Observation of direct and indirect magnetoelectricity in lead free ferroelectric (Na_0.5Bi_0.5TiO₃)–magnetostrictive (CoFe₂O₄) particulate composite

Abstract

A particulate composite consisting of 65 mol. % Na0.5Bi0.5TiO3 and 35 mol. % CoFe2O4 was synthesized, and it’s structure, microstructure, ferroelectric, magnetostrictive, magnetic, and direct/indirect magnetoelectric properties were studied. The composite showed different magnetization behaviour under electrically poled and un-poled conditions. The percentage change in magnetization as a result of poling is approximately −15% at 500 Oe magnetic field. Magnetostriction measurements displayed a value of λ11 = −57 × 10−6 and piezomagnetic coefficient δλ11/δH = 0.022 × 10−6 kOe−1 at 2.2 kOe for the composite. The maximum magnetoelectric output varied from 1350 mV/cm to 2000 mV/cm with change in the electrical poling conditions.