Comprehensive study of MFe2O4 (M=Co, Ni, Zn) nanostructures prepared by co-precipitation route

The phase analysis and average crystallite size of 11.8, 3.1, and 24.7 nm for MFe2O4 (M=Co, Ni, Zn) nano -particles (NPs) were analyzed by X-ray diffraction (XRD) patterns, respectively. The spherical and nano -platelets morphology of MFe2O4 (M=Co, Ni, Zn) was observed by High-Resolution Transmission electron microscopy (HRTEM). The peaks of Fe (2 P3/2), Fe(2 P1/2), Co (2 P3/2), Co(2 P1/2), Ni (2 P3/2), Ni (2 P1/2), Zn (2 P3/2), Zn (2 P1/2) and O (1 S) of the prepared nanostructures corresponding to octahedral and tetrahedral sites was observed X-ray photoelectron spectroscopy (XPS) spectra, respectively. Saturation magnetization of 37.4, 18.2, and 15.3 (emu/g) and coercive field of 525, 35.2, and 29.7 Oe of the prepared MFe2O4 (M=Co, Ni, Zn) nanostructures was recorded by M-H analysis at the applied field of & PLUSMN; 7 T. The shifting of the blocking temperature towards lower scale of about 300 K, 150 K, and 55 K for CoFe2O4, NiFe2O4, and ZnFe2O4 na-nostructures was determined by Zero field-cooled (ZFC) and field-cooled (FC) spectra, respectively. Spin -spin relaxation time 0.1677 x 10-15, and 0.0482 x 10-15 (s) and Spin-lattice relaxation time 0.829 x 10-14, and 2.865 x 10-14 (s) have been evaluated for NiFe2O4 and Zn Fe2O4 NPs, respectively from EPR spectroscopy. Super-paramagnetic time of 0.134 x 10-10, and 5.703 x 10-10 (s) was estimated from the EPR spectrum of the samples exhibiting less time required for NiFe2O4 than ZnFe2O4 NPs. The prepared NPs showing the su-perparamagnetic property can be used in biomedical applications such as drug delivery and magnetic re-sonance imaging (MRI).& COPY; 2023 Elsevier B.V. All rights reserved.