Formation and characterization of PrGa0.9Mg0.1O3 synthesized by a citric acid method

PrGa0.9Mg0.1O3 was synthesized by using a citric acid method. Compared with the sample prepared by the solid state technique, the sample synthesized by the citric acid method crystallized at a lower temperature. X-ray diffraction data indicated that a pure orthorhombic phase was formed at 1300 °C. PrGa0.9Mg0.1O3 showed a conductivity of 0.076 S/cm at 800 °C and an activation energy of 32.98 kJ/mol. Its average thermal expansion coefficient from 600 to 1000 °C was 11.9 × 10−6 K−1, which well matches with the NiO/YSZ anode and doped LaMnO3 cathode. A power density of 55 mW/cm2 and a short circuit current density of 200 mA/cm2 were obtained at 900 °C in a single fuel cell experiment by using PrGa0.9Mg0.1O3 as an electrolyte. This could be attributed to the existence of hole conduction in the sample.