Synthesis, characterization, and magneto-electric properties of (1−x)BCZT-xCFO ceramic particulate composites

Abstract

Synthesis of a new magnetoelectric [(1−x)(Ba0.85Ca0.15)(Zr0.1Ti0.9)O3-xCoFe2O4] (weight fraction x=0, 0.1, 0.2, 0.3, 0.4, 0.5 and 1) ceramic particulate composites with its structural characterization and magneto-electric properties have been reported here in this study. Lead free piezoelectric (Ba0.85Ca0.15)(Zr0.1Ti0.9)O3 (BCZT) and ferrimagnetic CoFe2O4 (CFO) were synthesized using sol-gel and combustion methods respectively. (1−x)BCZT-xCFO magnetoelectric composites were then synthesized by mixing of the calcined individual ferroic phases with required weight fractions. Powder X-ray diffraction studies indicate the coexistence of BCZT and CFO phases in the composites sintered at 1300°C. 0.5BCZT-0.5CFO composite showed high strain sensitivity (dλ/dH) of 52×10−9Oe−1, which is comparable to that of pure CFO (50×10−9Oe−1). A high piezoelectric voltage constant (g33) of 8×10−3 V m/N was measured for 0.8BCZT-0.2CFO sample. All the composites showed magnetoelectric effect and a high magnetoelectric coupling coefficient (αME) of 6.85 mV/cm Oe was measured for 0.5BCZT-0.5CFO composite at 1 kHz and a large ME coefficient of 115 mV/cm Oe at its resonance frequency. The effect of microstructure on the magnetoelectric properties of [(1−x)BCZT-(x)CFO] composites has been studied and reported here as a function of its piezoelectric (BCZT)/ferrite (CoFe2O4) content.