Synthesis of Sr-doped LaCrO3 powders by combustion method Influence of the fuel agent

Lanthanum strontium chromite (LSC) powders were synthesized by the combustion method, using five different fuels (urea, glycine, ethylene glycol, alpha-alanine, and citric acid). The ignition of the reagent mixture with urea takes a longer time, and more gases are released by combustion. A calcination step is essential for a good crystallization of the perovskite phase. X-ray diffraction patterns showed formation of perovskite phase and a small amount of SrCrO4 for the sample synthesized with urea after calcination. The crystallite sizes are in the range of 23-33 nm. Scanning electron microscopy revealed the porosity of the powders and the presence of agglomerates, formed by fine particles of different shapes. Thermogravimetric analysis showed a large mass loss for the sample synthesized with citric acid, probably caused by the absence of ignition, with primary polymerization of the precursor reagents.