The effect of organic coatings in the magnetization of CoFe2O4 nanoparticles

Abstract

Cobalt ferrite has attracted considerable attention in recent years due to its unique physical properties, such as high Curie temperature, large magnetocrystalline anisotropy, high coercivity, moderate saturation magnetization, large magnetostrictive coefficient, and excellent chemical stability and mechanical hardness. This work focuses on the neutron scattering results of the magnetic response characteristics of polysaccharide fucan coated cobalt ferrite nanoparticles for their application as a solid support for enzyme immobilization and other biotechnology applications. Here, we unambiguously show that surfactant coating of nanoparticles can significantly affect their magnetic response throughout the nanoparticle volume. While it has been recently suggested that oleic acid may preserve nanoscale magnetism in ferrites, we present evidence that the influence of oleic acid on the magnetic response of CoFe2O4 nanoparticles is more than a surface effect, instead pervading throughout the interior of the nanoparticle.