Reversible Oxygen-Ion Storage for Solid Oxide Cells
However, repeated charging (electrolysis) and discharging (fuel cell mode) can result in coarsening of particles and external layer formation. Both effects are not desired because they decrease the overall surface and thus the reaction kinetics. Adding secondary oxides to the Fe2O3 base material can mitigate those degradation phenomena. In the present study the effect of additions of Al2O3, CeO2, Mn3O4, Cr2O3, TiO2, SiO2, and MgO to the Fe2O3 base on the degradation properties is analysed. To this end, compacted samples are repeatedly oxidised and reduced in a laboratory furnace, where the conditions present in the ROB are simulated. Using X-ray diffraction and scanning electron microscopy it was found that among the tested oxides only MgO and Al2O3 could mitigate the layer formation and the particle coarsening to some extent.