Structural and Magnetic Property of Cr3+ Substituted Cobalt Ferrite Nanomaterials Prepared by the Sol-Gel Method

Abstract

Cobalt-chromium ferrite, CoCrxFe2−xO4 (x = 0–1.2), has been synthesized by the sol-gel auto-combustion method. X-ray diffraction (XRD) indicates that samples calcined at 800 °C for 3 h were a single-cubic phase. The lattice parameter decreased with increasing Cr concentration. Scanning electron microscopy (SEM) confirmed that the sample powders were nanoparticles. It was confirmed from the room temperature Mössbauer spectra that transition from the ferrimagnetic state to the superparamagnetic state occurred with the doping of chromium. Both the saturation magnetization and the coercivity decreased with the chromium doping. With a higher annealing temperature, the saturation magnetization increased and the coercivity increased initially and then decreased for CoCr0.2Fe1.8O4.

Recent Advances of Magnetic Nanomaterials in Bone Tissue Repair

“…The sol-gel method for preparing nano metal oxide is an ideal wet method. This method is based on the hydroxylation and condensation of molecular precursors in solution to form a “sol” of nanoparticles (Kayili and Salih, 2016 ; Lin et al, 2018a ; Wang J. et al, 2018 ; Bao et al, 2020 ). Gao, prepared Fe 3 O 4 nanoparticles under supercritical conditions by the sol-gel method (Gao et al, 2019 ).…”

“…Lin et al reported that monodisperse spherical Co-Cr-Ferrite nanomaterials can be easily prepared by co-condensation of Co(NO 3 ) 2 ·6H 2 O, chromium nitrate, Cr(NO 3 ) 3 ·9H 2 O, and iron nitrate using the sol-gel method. Co-Cr-Ferrite nanomaterials were prepared with excellent magnetic properties with stable monodisperse distribution (Lin et al, 2018a ).…”

57Fe Mössbauer study of CoCrxFe2-xO4 nano ferrite

“…Site A, B are respectively allocated by divalent; trivalent metal ions, and owing to un-equal magnetic moments on site A, and B, ferrites display spontaneous magnetization [2]. Synthesis protocol [3][4][5], substitutions and/or presence of various cations [6][7][8][9], post-preparation treatments, e.g. : thermal [10,11]; or no post-preparation thermal treatments [4,12], ion irradiation [6] etc.…”

“…Allocation of ions, and their relative population on A, B site can be used to control magnetic properties of ferrites. Thus, information on cationic distribution facilitate the understanding magnetic properties of spinel nano ferrites [6][7][8][9]. Sensible information on cationic distribution can be obtained from x-ray diffraction (XRD) [6,7,9,10], as well as from Mössbauer spectroscopy [13].…”

“…Thus, information on cationic distribution facilitate the understanding magnetic properties of spinel nano ferrites [6][7][8][9]. Sensible information on cationic distribution can be obtained from x-ray diffraction (XRD) [6,7,9,10], as well as from Mössbauer spectroscopy [13]. XRD data provides structural parameters (e. g. -grain diameter, cationic distribution, inversion parameter, oxygen parameter, dislocation density etc.…”