green synthesis of cofe2o4 ferrofluid: investigation of structural, magnetic and rheological behaviour

in this work, we report the green synthesis of cobalt ferrite (cofe2o4) nanoparticles ferrofluid by a modified co-precipitation method using glycyrrhiza glabra (licorice) roots as a surfactant, which is eco-friendly, non-toxic, and inexpensive. x-ray diffraction (xrd) analysis confirmed the purity of the spinel cofe2o4 structure. the average crystallite size, strain and lattice constant were 5 nm, 0.01, and 8.39 ao, respectively. fourier transform infrared spectrum (ftir) results demonstrated an absorption band at a wavenumber of 574 cm-1, indicating the presence of cobalt ferrite nanoparticles. transmission electron microscopy (tem) images showed that the sample contains well-dispersed and spherical nanoparticles with an average particle size of 12.6 nm. the magnetic properties of the fluid are confirmed from the (m-h) hysteresis curve. the hysteresis curve revealed the ferromagnetic nature of the particles, and the saturation magnetization (ms) is 56.6 emu/g. the rheological properties were studied with a variable magnetic field rheometer. the results showed that the rheological measurements comply with the structural and magnetic properties of the cfo ff by a green modified co-precipitation synthesis g. glabra, which can be used for various medical applications.