Magnetic field induced assembly of polyvinylpyrrolidone stabilised cobalt ferrite nanoparticles in different dispersion medium

Abstract

In this article, a report on the assembly of hydrophilic polyvinylpyrrolidone (PVP) stabilised CoFe2O4 nanoparticles (PVP@CoFe2O4) in different dispersion media under external magnetic field is presented. The assembly process in water, ethanol and toluene as solvent was studied. It was observed that water dispersion of PVP@CoFe2O4 gives longer chain-like assembly on applying unidirectional magnetic field as compared to ethanol which gives shorter chain assembly. On the contrary, in toluene dispersion, there is no such assembly on applying magnetic field. The effect of magnetic field on the assembly process was also studied. A possible explanation accounting for the observations is also presented.