Preparation and characterization of La and Cr co-doped SrTiO3 materials for SOFC anode

Using citric acid–nitrate process, La and Cr co-doped A-site deficient SrTiO3 (LSTC) materials were synthesized. The single-phase perovskite structure of LSTC materials can be obtained in airy atmosphere when the dopant content of chromium does not exceed 20 mol%. The LSTC material has excellent chemical compatibility with yttria-stabilized zirconia (YSZ) at 1400 °C. The particle diameters of LSTC powders calcined at 800 °C are all less than 60 nm. The LSTC pellet sintered in air at 1400 °C for 5 h shows a highly densified microstructure composed of polyhedral grains on a micron scale. At 800 °C, the conductivity of LSTC20 pellet is 1.96×10−3 S/cm in static air. The conduction activation energy of LSTC20 pellet is calculated to be 0.33 eV in the temperature range of 550–800 °C. The LSTC can be considered as a potential candidate anode material for SOFC with YSZ as electrolyte, but its conductivity needs to be further improved.