LaCoO3 synthesis by intensive mechanical activation

The paper reports the effect of mechanical activation of La2O3 and Co3O4, the precursors for obtaining LaCoO3. The precursors were mechanically activated in a Fritsch Pulverisette 5 planetary mill for different durations (150 rpm). The optimal mechanical activation duration of the precursor powder is 10 h. The grain size distribution of the precursor powder at different grinding times was determined. The morphology of the powder was examined by scanning electron microscopy. Analysis by X-ray diffraction revealed that, for the synthesis of LaCoO3 to take place, grinding alone is not enough, subsequent thermal treatment being crucial. The transformation of the mix in terms of its physical and chemical characteristics was carried out by thermal analysis. At the 10 h mechanical activation, the formation of LaCoO3 was found to be fully completed at 1200 °C. However, at longer grinding times the reaction is fully completed only at 1250 °C.