Synthesis and characterization of nickel ferrite magnetic nanoparticles

Nickel ferrite (NiFe2O4) nanoparticles are prepared by a polyvinyl alcohol (PVA) assisted sol–gel auto-combustion method. The structure, composition, morphology and magnetic properties of the gel precursor are characterized by powder XRD, FT-IR, TGA, HR-SEM, TEM, HR-TEM and VSM. XRD confirms the formation of single-phase nickel ferrite with space group of Fd3m and inverse spinel structure. The vibration properties of nanoparticles are analysed by FT-IR spectrum. The thermal decomposition of the gel precursors is investigated by TGA. HR-SEM and TEM images show that the particles have spherical shape with particle size in the range of ∼30 nm and consistent with XRD result. The magnetic properties of these nanoparticles are studied for confirming the ferromagnetic behaviour at room temperature.

. HR-SEM and TEM images confirmed that particles have spherical shape, narrow size and uniform distribution. Average crystallite size calculated from Scherrer's equation as 30 nm agrees well with the HR-SEM and TEM estimated average particle size about 30 nm. The obtained HR-TEM result is a good indication of each particle being a single crystal.Figure optionsDownload as PowerPoint slideHighlights
► The crystallite size was found to be 30 nm.
► From HR-SEM and TEM photographs are consonant with XRD.
► HR-TEM result is a good indication of each particle being a single crystal.
► High Ms (51.3 emu g−1) value of NiFe2O4 nanoparticles obtained.