Effect of ZnO nanoparticles on the dielectric and magnetic behavior of bismuth ferrite ceramics

Abstract

Bismuth ferrite (BiFeO₃, BFO) is a promising multiferroic material due to its inherent ferroelectric and antiferromagnetic properties; however, its practical applications are limited by weak dielectric and magnetic performance, as well as challenges in achieving pure-phase synthesis. In this study, the effects of incorporating zinc oxide (ZnO) nanoparticles at 0.5, 1, and 2 wt% on the dielectric and magnetic properties of BFO ceramics were systematically investigated. X-ray diffraction analysis confirmed that the addition of ZnO suppressed the formation of secondary phases and enhanced phase purity. A notable increase in relative density (from 94.3% to 98.2%) and a corresponding reduction in porosity were observed with increasing ZnO content. The dielectric constant significantly improved from 450 (pure BFO) to 4900 (2 wt% ZnO) at 1 kHz, albeit accompanied by a moderate rise in dielectric loss. Magnetic measurements revealed an increase in saturation magnetization from 0.18 to 0.44 emu/g and a decrease in coercivity from 810 to 560 Oe. These enhancements are attributed to the reduction of non-magnetic secondary phases, improved densification, and structural modifications induced by ZnO incorporation. Overall, the addition of ZnO presents an effective strategy for enhancing the multifunctional performance of BFO ceramics, making them more viable for advanced device applications.