Tailoring the structural, optical, photoluminescence, dielectric and electrical properties of Zn0·6Ni0·2Mg0·2Fe2-xLaxO4 (x = 0.00, 0.0125, 0.0250, 0.0375)

The green synthesis approach was used to manufacture the lanthanum modified spinel ferrites, which had the formula Zn0·6Ni0·2Mg0·2Fe2-xLaxO4 and were heated at 100 °C for 2 h. Through the use of XRD, FTIR, UV–visible, RLC study, four probe I–V, and PL spectroscopy the structural, optical, dielectric, electrical, and photoluminescence features were examined. XRD results confirmed that spinel ferrite have a cubic network. The substitution of La ions causes an overall increase in sample's lattice constants, which was credited to the disparity in ionic radii between Fe3+ (0.63 Aͦ) and La3+ (1.061 Aͦ) ions. From the XRD data, it was possible to compute the cationic distributions, oxygen positional parameters, tolerance factor, interatomic distances, bond lengths, bond length angles, and positional parameters. The computed Eg from the UV–Visible spectroscopy was decreased from 2.5 to 1.8eV. FTIR results revealed octahedral absorption band having 557.32–550.57 cm−1 range. The value of force constant from FTIR was revealed in the range of 2.27–2.21 dyne cm−1. The dielectric losses and constant are decreasing, whereas ac conductivity exhibited expanding behavior with high frequency. PL test result shows that La doping improves the material's light response, so the result showed that La-doped materials are suitable for magneto-optic devices. Electrical properties show that DC electrical resistivity decreases in the range of 1.65 × 10°5–5.01 × 10°3 Ω-cm. So, they are suitable for high-frequency circuits.