Preparation of nanostructured manganites SmMnO_3 and Sm_(0.5)Sr_(0.5)MnO_3 by mechanochemical synthesis method

摘要

The conventional ABO(3) perovskite-type oxides preparation methods are either complicated or time-consuming which cannot satisfy industrial needs. Mechanochemical processing as a low cost and high yield is a promising simple method. The effects of mechanical activation time and heat treatment on the microstructure of Sm2O3, SrCO3 and Mn2O3 powders were investigated. In the early stage of mechanical treatment partially short-range order amorphous occurs, very fine material with particle size less than 100nm was observed. SmMn2O5, SmMnO3 and Sm0.5Sr0.5MnO3 perovskites phases formation were started directly after heat treatment at 700 degrees C and subsequently increases with increasing temperature. SmMn2O5 thermally dissociated to SmMnO3 and MnO at 1200 degrees C. Magnetization of the heat-treated samples slightly varies in comparison to the as-milled.