Effect of molybdenum doping on the structural and magnetic properties of MnFe2O4 magnetic nanoparticles

Magnetic nanoparticles MnFe2-xMoxO4 (x = 0.00, 0.04, 0.08 and 0.10) have been prepared by wet coprecipitation method at calcination temperature 673 K. X-ray powder diffraction (XRD) was used to study the structural properties of the prepared samples, whereas the vibrating sample magnetometer (VSM) and Mössbauer spectrometry measurements (at T = 300 K and T = 77 K) were used to investigate the magnetic properties. The single-phase cubic spinel structure of the ferrites samples was confirmed by the XRD patterns, and a nonlinear variation in the crystalline size was revealed. VSM hysteresis loops confirmed the ferromagnetic behavior in all the samples with an increase in saturation magnetization with the molybdenum doping. Mössbauer spectra at 300 K showed a mixture of the magnetic sextet and central quadrupole doublet with enhancement in the magnetic sextet in the Mo-doped samples. Moreover, Mössbauer spectra at 77 K revealed the disappearance of the quadrupole doublet in all samples, indicating the enhancement of magnetic properties of manganese ferrites nanoparticles due to Mo-doping.