Enhancing magnetoelectric and optical properties of co-doped bismuth ferrite multiferroic nanostructures

In this research, we synthesize and characterize gadolinium (Gd) and chromium (Cr) co-doped multiferroic bismuth ferrite (BiFeO3). Un-doped and doped BiFeO3nanostructures were fabricated by chemical solution deposition (CSD) technique using precursor solutions of Bi, Fe, Gd and Cr based salts. X-ray diffraction (XRD) analysis confirmed crystalline BiFeO3with a tendency towards phase transition from rhombohedral to orthorhombic structure due to co-doping. Crystallite size was found to vary from 68 to 25 nm with increasing Cr doping. Gd/Cr co-doped BiFeO3also demonstrated a significant reduction in the optical band gap energy from 2.03 to 1.71 eV. Vibration Sample Magnetometer (VSM) results confirmed improved ferromagnetic properties of synthesized materials. A substantial enhancement of magnetization of 6 emu/gm was obtained for 5% Gd + 6% Cr doped multiferroic. Electric polarization measurements (P-E) displayed ferroelectric nature of the samples with a maximum remnant polarization of 0.23 μC/cm2. Co-existence of improved ferromagnetic and ferroelectric orders has been shown in co-doped BFO. Magnetoelectrc measurements displayed an outstanding results with many folds increase in magnetoelectric coefficient, αme(6.5 V.cm-1.Oe-1). The synthesized multiferroics may find potential application in memory devices.