Preparation and characterization of La0.9Sr0.1Ga0.8Mg0.2O3 − δ thin film on the porous cathode for SOFC

A dense and crack-free La0.9Sr0.1Ga0.8Mg0.2O3 − δ thin film has been prepared by RF magnetron sputtering. The XRD, FESEM, XPS and four-probe technique are employed to characterize the La0.9Sr0.1Ga0.8Mg0.2O3 − δ film. Results show that after annealing at 1000 °C, the La0.9Sr0.1Ga0.8Mg0.2O3 − δ film presents a polycrystalline perovskite structure with grain size of 100–300 nm. XPS data show that both La and Ga are in their +3 state. Sr element has two chemical states which are related to Sr2+ in the perovskite lattice and SrO1 − δ suboxide. The O 1s spectrum also shows two chemical states which can be assigned to molecularly adsorbed O2 species and O2− in the lattice. The electrical conductivity reaches to 0.093 S cm−1 at 800 °C. The microstructure and conductivity analysis indicates that the La0.9Sr0.1Ga0.8Mg0.2O3 − δ thin film prepared by RF magnetron sputtering is suitable for intermediate temperature Solid oxide fuel cell.