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 Mn 0.6 Zn 0.4 La x Fe 2− x O 4 ( 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 La 3+ 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 La 3+ ion content. The M S of Mn 0.6 Zn 0.4 La 0.09 Fe 1.91 O 4 was 58 emu/g, which could be potential hyperthermia in biomedical application.