synthesis and characterization of ag-y co-doped mn-co spinel for solid oxide fuel cell application

Mn-co spinel coating for solid oxide fuel cell interconnects shows a suitable thermal expansion match, acceptable electrical conductivity, and good structural stability. in this paper, the addition of different amounts of ag and y as dopants on the physical and electrical properties of the mn-co spinel is investigated to improve the coating performance. first, the doped and co-doped powders were successfully synthesized using the pechini sol-gel method. the synthesized powders were then characterized using x-ray diffraction and field emission scanning electron microscopy. the results confirmed that ag was not completely doped into the spinel structure and instead acted. as an additive, whereas y caused mn3o4 impurity phase formation at higher mol%. next, the powders were pressed and sintered at different temperatures (950 and 1050 °c) to evaluate the effect of dopants on the sintering and electrical behavior of the samples. finally, the electrical conductivity of the samples was evaluated using a 2-probe direct current technique. although results showed that room temperature electrical conductivity increased upon doping, adding y had a better effect on conductivity than ag.