CuMn 1.7 Fe 0.3 O 4-RE 2 O 3 (RE = Y, Gd) bilayers as protective interconnect coatings for solid oxide cells

Efficient replacement of materials based on critical elements such as cobalt is one of the greatest challenges facing the field of solid oxide cells. New generation materials, free of cobalt show potential to replace conventional materials. However, these materials are characterised by poor ability to block chromium diffusion. This article described the study of CuMn 1.7 Fe 0.3 O 4 (CMFO) spinel combined with single metal oxide (Y 2 O 3 or Gd 2 O 3 ) thin films as protective coatings for steel interconnects. CMFO was examined using XRD and TPR. Coated steel samples were oxidised in an air atmosphere at 700 degrees C for 4000 h. The coatings and oxide scale microstructures and cross-sections were examined by CRI, XRD, and SEM-EDX. The electrical properties of the steel-coating system were evaluated using Area Specific Resistance measurements. Based on the results obtained, it can be concluded that the use of thin layers of rare earth oxides allowed for better blocking of chromium diffusion.