Effect of Gd3+ substitution on physicochemical properties of superparamagnetic Fe3O4 nanoparticles

The present study depicts physicochemical characteristics of Gd3+ modified Fe3O4 nanoparticles synthesized via the sol-gel combustion method. Structural, microstructural, optical, electrical, and magnetic characteristics were investigated. X-ray diffraction studies demonstrated that all the compositions exhibit cubic crystallinity and phase pure crystal structure with space group $$Fd\bar{3}m$$ . FESEM micrographs depicted that the average crystallite size increases from 15.35 nm [x = 0] to 23.74 nm [x = 0.10] with increasing Gd3+ content. FTIR spectra of the compositions show bend at 522 cm− 1 belonging to Fe–O stretching, which confirms the formation of ferrite nanoparticles. Photocatalytic activity of Fe(3−x)GdxO4 nanoparticles with x = 0 and 0.10 was carried out using methylene blue (MB) dye under UV light. Dielectric studies revealed that the dielectric constant decreases due to the incorporation of Gd3+ ion in the Fe3O4 crystal lattice. Negligible coercivity and remnant magnetization revealed the superparamagnetic behavior for all the compositions and it was observed that saturation magnetization decreases with increasing Gd3+ concentration. Magnetic recyclability illustrated the reusability of Gd3+ modified Fe3O4 nanoparticles.