Optimization of LaMO3 (M: Mn, Co, Fe) synthesis through the polymeric precursor route

LaMO3 (Me: Mn, Co, Fe) powders were synthesized through a Pechini-type polymerizable complex route, based on the ability of citric acid (CA) to form stable metal chelates and the polyesterification between CA and ethylene glycol (EG). The effect of the molar ratios of reactants (CA:total cations = 1-4 and EG:CA = 1-3) on the precursors and the final powders was studied. The gelation procedure was monitored through continuous conductivity measurements. The calcination reactions were recorded using TG/DTA measurements, while XRD and FTIR were used for the characterization of the precursors and the final products. The results indicated that the polymerizable complex method can be successfully applied for the preparation of LaMO3. The formation requires a 3-h calcination at 600 °C. The molar ratios citric acid:total cations = 2 and ethylene glycol:citric acid = 3 are the most favorable ratios for the synthesis of LaMO3.