Structural and dielectric studies of Zr and Co co-substituted Ni0.5Zn0.5Fe2O4 using sol-gel auto combustion method

Zr and Co substituted Ni0.5Zn0.5 ZrxCuxFe2−2xO4 with x values varies from the 0.0 to 0.4 in steps of 0.08 wt% ferrites synthesized by using sol-gel auto combustion method. The XRD patterns give evidence for formation of the single phase cubic spinel. The lattice constant was initially decreased from 8.3995 Å to 8.3941 Å with dopant concentration for x = 0.00–0.08 thereafter the lattice parameter steeply increased up to 8.4129 Å fox x = 0.4 with increasing dopant concentration. The estimated crystallite size and measured particle sizes are in comparable nano size. The grain size initially increased 2.3137–3.0430 µm, later it decreased to 2.2952 µm with increasing dopant concentration. The prepared samples porosity shows the opposite trend to grain size. The FT-IR spectrum for prepared samples shows the Fd3m (O7h). The wavenumber for tetrahedral site increased from 579 cm−1 to 593 cm−1 with increasing dopant concentration and the wavenumber of octahedral site are initially decreased from 414 cm−1 to 400 cm−1 for x = 0.00 to x = 0.08 later increased to 422 cm−1 with increasing dopant concentration. The dielectric constant increased from 8.85 to 34.5127 with dopant increasing concentration. The corresponding loss factor was fallows the similar trend as dielectric constant. The AC conductivity increased with increasing dopant concentration from 3.0261 × 10−7 S/m to 4.4169 × 10−6 S/m. Keywords: Sol-gel auto combustion, XRD, SEM, FT-IR, Dielectric constant, Dielectric loss