| Abstract: |
This study investigates the multiferroic properties of bismuth-based metal oxide nanostructures, focusing on BiFeO₃ (BFO), Bi₂Fe₄O₉, and Bi₅Ti₃FeO₁₅ systems. Multiferroic materials, which simultaneously exhibit ferroelectric and magnetic ordering, represent a frontier in advanced functional materials with significant potential for next-generation memory devices and sensors. Through comprehensive structural, magnetic, and electrical characterization, we examine how nanostructuring influences the coupling between ferroelectric and magnetic properties in these systems. Hydrothermal synthesis methods were optimized to produce nanoparticles, nanorods, and thin films with controlled morphology and composition. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, and ferroelectric measurements revealed size-dependent enhancement of multiferroic properties, with critical dimensions below 100 nm showing significant improvements in magnetoelectric coupling coefficients. Notably, the BiFeO₃ nanoparticles with average diameter of 45 nm exhibited a magnetoelectric coupling coefficient of 18.5 mV/cm•Oe, representing a 37% enhancement compared to bulk counterparts. Temperature-dependent measurements confirmed room temperature multiferroicity, while substitutional doping with rare-earth elements demonstrated further property optimization potential. These findings provide critical insights for rational design of bismuth-based multiferroic nanostructures for technological applications. |
