Magnetic and Structural Phase Transition in Iron Oxide Nanostructures

Among various materials of interest iron oxide is a promising candidate owing to its unique physical and chemical properties. In this research work growth of iron oxide nanostructures is carried out using sol-gel method. The concentration of the sol is varied as 1.8 mM, 1.4 mM, 1.0 mM and 0.6 mM. It can be seen that molarity of the sol not only affects the phase transition from magnetite to maghemite but also strongly affects the magnetic properties. Low concentration results in formation of magnetite and maghemite mixed phases whereas high concentration results in phase conversion to pure magnetite phase. Saturation magnetization slightly decreases as the phase conversion from magnetite to maghemite takes place.