Synthesis and characterization of magnetic nanoparticles of cobalt ferrite coated with silica

Daniely Ferreira de Queiroz 1, Emerson Rodrigues de Camargo 2, Marco Antonio Utrera Martines 1

1Institute of Chemistry, Federal University of Mato Grosso do Sul, Cidade Universitaria, Campo Grande, MS 79074-460, Brazil

2Department of Chemistry, Federal University of São Carlos. Rod.Washington Luis km 235, CP 676 São Carlos SP, 13565-9905. Brazil

*corresponding author e-mail address: | 6603386498

Biointerface Research in Applied Chemistry, Volume 10, Issue 1, 2020, 4908 – 4913,


There are several methods available for magnetic nanoparticles (MNP) synthesis, and in this study the coprecipitation method is employed. The cobalt ferrites (CF) were prepared using aqueous solutions of Co2+ and Fe3+ chloride with a stoichiometry proportion of Co:Fe = 1:2. Thus, the aging temperatures were 27, 27/98, 60, 80 and 98 ºC, during which the precipitation occurred at 27 °C and the aging one at 98 °C for the FC27/98 sample. As a result, the study showed that a single crystal phase material was obtained at the aging temperature of 98 °C during 1 h and with a mean particle size of 42 nm ± 7.4 nm and degree of polydispersity of 18%. The FC98/SiOH coated nanoparticle had a surface area of 11 m2 g-1, saturation magnetization of 10.05 emu g-1 a mean particle size of 773.4 nm ± 131.1 nm and a degree of polydispersity of 17 %. It was possible to confirm that it had a silica coating of cobalt ferrite nanoparticles by DRIFT and EDX indicated the presence of silica.

Keywords: coprecipitation; CoFe2O4; SiO2; magnetic nanoparticles; nanotechnology