Influence of citric acid molar ratio on the sintering behavior of nanocrystalline BaCe0.8Sm0.2O(3-delta).

The samarium-doped barium cerate (BaCe0.8Sm0.2O(3-delta), BCS) nano crystalline powders were synthesized via citric-nitrate method. The BCS nanopowders were prepared with various molar ratio of citric acid to metal nitrate. The pure perovskite structure was obtained from the BCS calcinated at 1200 degrees C and its crystalline size was increased with increase of the molar ratio citric acid to metal nitrate, while the aggregated particle size was significantly decreased as increasing the molar ratio. Also, excellent densification behavior was observed when high molar ratio of citric acid to metal nitrate was used. It was clarified that the molar ratio of citric acid determines the aggregated particle size and, in turn, finial microstructure after sintering.