Comparison of Cu1.3Mn1.7O4 spinels doped with Ni or Fe and synthesized via wet chemistry and solid-state reaction methods, designed as potential coating materials for metallic interconnects

The influence of the method applied to synthesize Cu-Mn-O spinel was evaluated. The methods selected for the investigation were EDTA gel processes and solid-state reaction synthesis. From the obtained powders, sinters were prepared and assessed in terms of their properties as potential coating materials. Additionally, the influence of Ni and Fe dopants was evaluated. The results show that the EDTA gel processes method seems to be more suitable for spinel synthesis. This method yields spinels that exhibit electrical conductivity above the required threshold (>50 S/cm) over a temperature range of 400–850 °C, and it also ensures continuous spinel matrices and high spinel content. Spinels obtained via solid-state reactions exhibit inferior properties. A higher concentration of Ni allows electrical conductivity to be improved further, while the opposite tendency is observed for Fe. Finally, it was shown that spinels obtained via EDTA gel processes are promising protective-conducting coating materials for SOEC/SOFCs steel interconnects.