CO2 and O2 sensing behavior of nanostructured barium-doped SmCoO3

Single-phase perovskites, Sm1−xBaxCoO3 (x = 0, 0.1), were prepared by a simple aqueous solution method using stoichiometric amounts of the corresponding nitrates and citric acid. X-ray diffraction showed that the introduction of barium reduced the temperature of formation of the perovskite and yielded nanostructured Sm0.9Ba0.1CoO3. The evaluation of nanostructured Sm0.9Ba0.1CoO3 as a gas sensor material was made through the electrical characterization of sintered thick films, in flowing O2 and CO2. The results clearly indicate good sensitivity to these gases at 373 °C and 410 °C, respectively.