Thermal and crystalographic studies of mixture La2O3-SrO prepared via reaction in the solid state

The compound obtained via state solid reaction of the La2O3 and SrO oxides and expose the room atmosphere shows the crystallographic data of the compo und reported as La2SrOx. However, thermogravimetric, differential thermal a nalysis and XRD with controlled temperature indicated that the stoichiometr y of the compound is 2La(OH)(3)-SrCO3, which structural parameters were det ermined by using the Rietveld method. It was verified that when the compoun d exposed at room atmosphere, the mixture oxide absorbs H2O and CO2 produci ng hydroxide and carbonate of lanthanum and strontium, respectively, which thermal decomposition occurs by the same steps, producing the La2O3-SrO.