Structural, optical, and magnetic properties of Ni${}_{1-x}$Zr${}_x$Fe${}_2$O${}_4$ nanostructures prepared by sol-gel synthesis

Magnetic nanoparticles have been attracting more and more attention as important magnetic materials. In this work, to improve the electrical and magnetic properties, we substituted nickel atoms with zirconium. Magnetic nanoparticles of Ni${}_{1-x}$Zr${}_x$Fe${}_2$O${}_4$ with x = 0.1, 0.2, 0.3, and 0.4 have been synthesized via sol-gel method. The microstructures, magnetic, electrical, and absorption properties of the Ni${}_{1-x}$Zr${}_x$Fe${}_2$O${}_4$ nanostructures were investigated. The saturation magnetization and coercivity of Ni${}_{1-x}$Zr${}_x$Fe${}_2$O${}_4$ nanostructures increased with the increase in Zr atomic loadings to 0.3 mol. The measurement results showed that the absorption properties of the Ni${}_{1-x}$Zr${}_x$Fe${}_2$O${}_4$ nanostructures strongly depend on the Zr atomic loading from 0.1 to 0.4 mol. The high absorption performance is mainly due to the magnetic and dielectric losses of the composite material, and the results showed that the prepared nanostructures were composed of smaller size nanoparticles and had excellent electromagnetic absorption properties. This study shows that by using a lower atomic content of Zr, it is possible to produce larger nanoparticles and less saturation magnetization.