Microwave assisted synthesis of fine magnetic manganese ferrite particles using co-precipitation technique

Co-precipitation technique results in the better homogeneity of the particles as compared to the conventional ceramic technique. However, there is a range of concentration ratios of the reacting compounds which result in the particles of required properties. In this work, the co-precipitation technique has been utilized to synthesize homogeneous ferrite nano particles. The manganese ferrite has been synthesized using MnCl2, 4H2O, FeCl3, 6H2O and NaOH. The standard co-precipitation route was used to synthesis fine particles. First we dissolved the metallic salts of Manganese and iron in distilled and de ionized water, the metal ion solution was then reacted with the NaOH solution. The resulting precipitate was brought to temperatures of 60 degree C to 100 degree C for digestion times of 20 minutes and 60 minutes. The subsequent digestion process was performed to obtain equilibrium particle size. Different effects were studied such as effect of concentrations, effect of duration on digestion and digestion temperature on the structural properties of the particles. It was studied that for the formation of Mann ferrite an increase of pH value up to 12.5 accelerated the formation of the ferrite. But a further increase of pH up to 14 led to a reduction of the ferrite yield. The solutions were then oven dried or treated with microwaves. The effect of conventional thermal treatment and of the microwave treatment was compared and it was found that the microwave treatment results in greater spontaneous magnetization. The powder x ray diffraction technique was used to examine the ferrite phase of the particles. The particle size was calculated by Scherer's formula using the broadening of the characteristic (311) peak of the spinel ferrite in the range of 18.7-23.9 nm.