Preparation of Nickel Ferrite Nanoparticles and its Application in Nanofluids

The aim of the present research work was to prepare NiFe2O4 nanoparticles using standard wet chemical method namely sol-gel auto-combustion with a view to study them in heat transfer application. The prepared nanoparticles of NiFe2O4 were then applied to prepare nanofluid with deionised water as a base fluid. The characterization of the prepared NiFe2O4 nanopowder is done by X-ray diffractometer (XRD) technique. The XRD pattern was recorded at room temperature. The analysis of XRD pattern was carried by standard software suggests that prepared nickel ferrite nanopowder possess single phase cubic spinel structure. The lattice constant was obtained by using XRD data reasonably agree with the reported values. The mean size of the particle was estimated through XRD pattern, in which the most intense peak (311) was considered to obtain full width at half maxima (FWHM). The Scherrer formula was used to obtain average crystallite size which was found to be 33 nm. The surface morphology of the prepared NiFe2O4nanopowder was studied by means of scanning electron microscopy (SEM) technique. The average grain size determined by linear intercept method was found to be of the order of 40 nm. The SEM image shows formation of spherical grains with some agglomeration. The prepared nanofluid of nickel ferrite was used to estimate thermal conductivity. It was found that, the thermal conductivity of NiFe2O4nanofluid was increased compared to deionised water.