Magnetic fluids can be prepared from
nanomagnetic materials. Synthesis conditions are methods are tiresome and
require high end technological tools.
Copper ferrite particles can be prepared from copper oxide and iron
oxide. These starting precursors are mixed in a mortar. For fine mixing,
toluene can be added. Some 10 hours of mixing and subsequent sintering will
yield fine copper ferrite particles. These particles are then cooled by pouring
liquid nitrogen on it. Mixing using toluene is repeated for about one hour now.
Sintering to 1200 K will yield ultrapure copper ferrite. This copper ferrite
material is then ball milled for several hours keeping rpm of milling unit at
its maximum (a minimum of 750 rpm for steel balls and 500 rpm for tungsten
carbide balls). Now ultrafine nanoparticles of copper ferrite are ready. Mix
oleic acid and kerosene with fine powder and make a paste. This paste you heat
using oven at around 350 Kelvin for two hours.
Take the sample out from oven, mix kerosene again to make it a solution.
This solution is ball milled keeping some low rpm (a maximum of 250 rpm for
steel balls and 100 rpm for tungsten carbide balls). Now magnetic fluid is
ready. We can undergo various characterization studies such as X-ray
diffraction, neutron diffraction, electron diffraction, low energy ion
scattering, scanning electron microscopy, transmission electron microscopy etc.
on these magnetic fluids.
