A high performance nano-structure conductive coating on a Crofer22APU alloy fabricated by a novel spinel powder reduction coating technique

A nano-structure conductive coating was fabricated on a Crofer22APU alloy interconnect by an original coating strategy using Mn_0.9Y_0.1Co₂O₄ (MYC) novel spinel nanocrystalline powder. A unique treatment method by which the spinel powder was reduced was used to prepare the green coating. The resulting coating was about 12 μm in thickness, and was composed of MYC nanocrystalline with an average particle size of about 100 nm. The coating was well adhered with the substrate alloy. Less than 4 mΩ cm² of the area specific resistance (ASR) was obtained, and no obvious degradation was observed for a coated alloy (whose coating thickness was about 30 μm) after operated at 800 °C for 538 h under seven thermal cyclings. The coated alloy exhibited excellently electrical performance and long-term stability compared with the uncoated one. The exploration of the novel spinel powder reduction coating technique for alloy interconnect to obtain cheap coatings with excellent microstructure and performance showed a promising prospect for the practical application of solid oxide fuel cells (SOFCs).