Investigation of Structural, optical, and Magnetic Properties of Ytterbium- Aluminum ions co-doped bismuth ferrite nano-Ceramics

This study looks at the structural, optical, and magnetic properties of Al3+ and Yb3+ ions co-doped bismuth ferrite (BFO) nanoparticles made using the sol-gel method. X-ray (XRD) analysis revealed the production of a single-phase perovskite structure, with decreasing average crystallite size as the concentration of co-dopants increased. The inherent ionic radii mismatch inhibits grain formation, resulting in a reduction in size. The diffuse reflectance spectroscopy (DRS) revealed a decrease in optical band gap energy from 2.111 eV to 2.022 eV as the concentration of co-dopants increased, which is attributed to the introduction of a new energy level in the forbidden region, optimizing visible light absorption. Furthermore, the vibration sample magnetometer (VSM) results revealed a significant increase in saturation magnetization from 1.239 emu/g to 3.156 emu/g. This considerable magnetic increase is explained by the presence of co-dopants (Al3+ and Yb3+) in the host material, which effectively suppresses the natural cycloidal spiral spin structure that causes non-zero net magnetization. These results confirmed that the partial substitution of the co-dopants strategy has effectively tailored the properties of the pristine BFO, making the resulting nanoparticles promising candidates for the application in photocatalysis, magnetic memory storage, MRI contrast agents, and targeted drug delivery.