화학공학소재연구정보센터
Journal of Power Sources, Vol.378, 125-133, 2018
CuMn1.8O4 protective coatings on metallic interconnects for prevention of Cr-poisoning in solid oxide fuel cells
Cr-poisoning of the cathodes due to the presence of metallic interconnects is detrimental to the performance of intermediate temperature solid oxide fuel cell stacks. Applying a protective coating on the interconnect is an effective solution to preventing Cr-poisoning. In this study, the application of a protective CuMn1.8O4 spinel coating is explored. Dense coatings are deposited on both metallic flat plates and meshes by electrophoretic deposition followed by thermal densification steps. The coating is found to be a mixture of Mn3O4 and cubic spinel phases at room temperature but is a pure cubic spinel phase between 750 degrees C and 850 degrees C. A reaction layer between the Cr2O3 scale at the coating/interconnect interface and CuMn1.3O4 coating is found to be a mixture of (Cu,Mn,Cr)(3-x),O-4 cubic spinel phases with Cr-rich precipitates believed to be Cr2O3, indicating that the coating layer acts as a Cr getter. Solubility experiments show that 1 mol of the CuMn1.3O4 phase can getter at least 1.83 mol of Cr2O3 at 800 degrees C. Electrochemical testing of cells in the presence of coated interconnects show that the CuMn1.8O4 coating getters Cr effectively for 12 days at 800 degrees C, leading to no performance loss of the cell due to Cr-poisoning.