Charge transfer mediated magnetic response of cobalt ferrite nanoparticles

摘要

Herein, we have performed rational surface modification of CoFe2O4 nanoparticles (NPs) to tune its room temperature ferrimagnetic properties by using different non-ionic surfactants. The NPs have been prepared by surfactant-assisted chemical co-precipitation technique with a narrow size distribution. For our study, we have chosen four non-ionic surfactants of triton X and tween group having different chain-lengths. Interestingly, we have found that surfactant co-ordinated magnetic NPs show a maximum of similar to 94% increase in coercivity along with a considerable decrease in magnetization as compared to the bare one. Systematic investigation reveals that both the nature and number of surfactant's head group and chain-length of its alkyl tail group have a remarkable impact on the magnetic properties of CoFe2O4 NPs. We believe that the tuned magnetic response of CoFe2O4 NPs depending on the nature of the surface binding ligand would open up many new opportunities as well as enhance their beneficial activities toward diverse application fields. (C) 2015 Elsevier B.V. All rights reserved.