Performance evaluation of LSM-metallic interconnect composite films prepared by plasma sputtering method

The effect of the La_0.67Sr_0.33MnO₃ (LSM) coating layer on the electric properties of the Fe-Cr alloys (Crofer22 and equivalent ZMG232) and the alloys themselves are examined in a hot air environment. A LSM thin film is coated on these materials using pulsed DC magnetron sputtering. The film is amorphous but is transformed into a perovskite structure after annealing at different temperatures and times. The coating structures and surface morphologies are analysed using Xray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The result shows that the LSMO thin film on Crofer22 APU is good for compaction and adhesion. Thus, it could prevent the growth of oxides and the diffusion of Cr element to avoid cathode poisoning and decline of conductivity in solid oxide fuel cells (SOFCs) at high temperatures.