Tailoring the super-paramagnetic nature of MgFe2O4 nanoparticles by In3+ incorporation

•In3+ doped MgFe2O4 nanoparticles are prepared by sol-gel method.•XRD and IR showed the formation of pure spinel ferrites.•XPS confirmed the valance states as Fe3+, Mg2+, In3+ and O2−.•Super-paramagnetic nature of nanoparticles is observed.•Blocking temperature is obtained at RT under applied field of 250 Oe. MgFe1−xInxO4 nanoparticles (where x=0.00, 0.04, 0.08, 0.12 and 0.16) have been prepared by sol-gel method using citric acid. The appearance of two distinct bands corresponding to tetrahedral and octahedral occupied MO bonds has been demonstrated in Fourier Transform Infra Red spectra (FT-IR). X-ray powder pattern confirmed the presence of a cubic spinel phase. X-ray Photoelectron Spectroscopy (XPS) has been employed to confirm the valence states of the metal ions present. Mössbauer spectroscopy shows the sextet for pristine sample and on In3+ doping the super-paramagnetic doublet becomes prominent. AC susceptibility profiles shows transition from single domain structure to super-paramagnetic particles on doping. The magnetic properties have been studied using Vibrating Sample Magnetometer (VSM), here the M-H and M-T curves showed the formation of super-paramagnetic nanoparticles at room temperature, where the saturation magnetisation (Ms), remnant magnetisation (Mr) and coercivity (Hc) values decreased with In3+ incorporation.