Structural, spectral, dielectric and photocatalytic studies of Zr-Ni doped MnFe2O4 co-precipitated nanoparticles

In this study the Mn 1–2x Zr x Fe 2−y Ni y O 4 nanoparticles fabricated by co-precipitation technique were investigated. Thermo-gravimetric analysis (TGA) exhibited the annealing temperature of the nanoparticles ~990 °C. Cubic spinel structure of Mn 1–2x Zr x Fe 2−y Ni y O 4 nanoparticles was confirmed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) analysis. Crystallite size was calculated by XRD data and found in the range of 32–58 nm. Photocatalytic activity of Mn 0.92 Zr 0.04 Fe 1.88 Ni 0.12 O 4 /graphene nanocomposites was tested by degrading methylene blue (MB) under visible light irradiation. The MB was almost completely degraded in the presence of Mn 0.92 Zr 0.04 Fe 1.88 Ni 0.12 O 4 -graphene nanocomposites under visible light irradiation. Dielectric parameters were also investigated in the frequency range 1×10 6 –3×10 9 Hz. An overall decrease in the values of dielectric constant, dielectric loss and tangent loss was observed on account of the substitution of Zr and Ni with Mn and Fe cations.