Evaluation of using protective/conductive coating on Fe-22Cr mesh as a composite cathode contact material for intermediate solid oxide fuel cells

An uncoated and MnCo_1.9Fe_0.1O₄ (MCF) coated Fe-22Cr meshes were dipped into LaNi_0.6Fe_0.4O_3−δ (LNF) slurry to form a continuous protective/conductive layer for Crofer22APU interconnect. After aged these samples at 800 °C for 1000 h, energy dispersive X-ray (EDX) results concluded that: if the deposition of the protective coating was not enough to form a dense and continuous layer across the width of the mesh, then the use of MCF spinel layer is not enough to prevent chromium migration. For mesh-LNF/interconnect structure the area specific resistance (ASR) value of 0.0425(2) Ω cm² was stable for 400 min at 800 °C, indicating initial good adherence between both materials. After aged this structure at 800 °C for 1000 h, without applying a current source, X-ray micro-diffraction (XRMD) results, performed at the rib and channel of the interconnect, revealed that the LNF material is acting as a protective layer. Moreover, X-ray photoelectron spectroscopy (XPS) analysis indicated that manganese is concentrated on the mesh/LNF contact surface.