Structural, morphological and magnetic study of hydrothermal La3+ substitution in Mn-Zn nanoferrites

Magnetic nanoparticles were one of the most promising materials for targeted magnetic hyperthermia application due to the excellent magnetic properties. In this work, the magnetic nanoferrite of Mn0.6Zn0.4LaxFe2-xO4 (x=0.09, 0.1, 0.15, 0.2, 0.25 and 0.3) was synthesized by the hydrothermal method. Various physical properties of samples have been characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), transmission electron microscopy and vibrating sample magnetometer. XRD results revealed that the lattice constants a(t) and crystallite size of the Mn-Zn nanoferrites decreased with increasing La3+ content. The characteristic absorption bands of spinel nanoferrites and polyethylene glycol were observed in the FTIR spectra. FTIR results indicated that polyethylene glycol was coated on the Mn-Zn nanoferrites successfully. The saturation magnetization (M-S), magnetic moment (M-r) and anisotropy constant (K) were affected by La3+ ion content. The M-S of Mn0.6Zn0.4La0.09Fe1.91O4 was 58 emu/g, which could be potential hyperthermia in biomedical application.