Preparation of nanostructured manganites SmMnO₃ and Sm_0.5Sr_0.5MnO₃ by mechanochemical synthesis method

The conventional ABO₃ 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 100 nm was observed. SmMn₂O₅, SmMnO₃ and Sm_0.5Sr_0.5MnO₃ perovskites phases formation were started directly after heat treatment at 700 °C and subsequently increases with increasing temperature. SmMn₂O₅ thermally dissociated to SmMnO₃ and MnO at 1200 °C. Magnetization of the heat-treated samples slightly varies in comparison to the as-milled.