Effect of Concentration of Zr4+ and Ni2+ Dopants on Electrical, Magnetic and Y–K Angle of Mg–Cu Complex Spinel Nanoferrites

Abstract

The complex Mg–Cu nanoferrites with composition Mg0.5Cu0.5Fe2−2xNixZrxO4 (0.00≤x≤0.80) were synthesized by incorporating dopants Zr4+ and Ni2+ with the help of chemical co-precipitation method. The synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), dc electrical and magnetic properties through laboratory-made two-probe resistivity apparatus and vibrating sample magnetometer (VSM). XRD confirmed the formation of single phase spinel nanoferrites having crystalline size in range 16–29 nm. The particle size (t) and lattice parameter (a) increase with the increase in concentration of dopants. The XRD results are in good agreement with SEM results. FTIR give valuable information about the presence of tetrahedral (A) and octahedral (B) sites by considering higher and lower frequency bands, respectively. The electrical properties, e.g. dc electrical resistivity (ρd), drift mobility (μd) and activation energy (E), were calculated. Resistivity data confirm semiconducting behavior of material. And it is observed that an abrupt increase in resistivity occurs up to x=0.40. While further increase in dopants concentration leads to decrease in resistivity. Magnetic hysteresis loops confirmed soft nature of synthesized material. Interesting magnetic behavior is observed that up to x=0.40 the value of saturation magnetization (Ms), remanence (Mr) and Bohr magneton (nB) increase and after that decrease in trend occurs. For x=0.40, minimum coercive force (Hc) is observed. Y–K angle increases with increase in dopant concentration. So it is confirmed that the incorporation of dopant in small amount (x≤0.40) enhances magnetic properties and further increase of Zr4+ can weaken magnetic properties.