Abstract: Chitosan functionalized Fe3O4-Au core shell
nanoparticles have been prepared using a two-step wet chemical
approach using NaBH4 as reducing agent for formation of Au in
ethylene glycol. X-ray diffraction studies shows individual phases of
Fe3O4 and Au in the as prepared samples with crystallite size of 5.9
and 11.4 nm respectively. The functionalization of the core-shell
nanostructure with Chitosan has been confirmed using Fourier
transform infrared spectroscopy along with signatures of octahedral
and tetrahedral sites of Fe3O4 below 600cm-1. Mössbauer
spectroscopy shows decrease in particle-particle interaction in
presence of Au shell (72% sextet) than pure oleic coated Fe3O4
nanoparticles (88% sextet) at room temperature. At 80K, oleic acid
coated Fe3O4 shows only sextets whereas the Chitosan functionalized
Fe3O4 and Chitosan functionalized Fe3O4@Au core shell show
presence of 5 and 11% doublet, respectively.