Unraveling the effects of asymmetric interfaces in three-dimensional solid oxide fuel cells

The three-dimensional (3D) structuring of interfaces in solid oxide fuel cells (SOFCs) is a valuable morphological approach that maximizes the reaction area and ion transfer pathways, enabling operation at lower temperatures. To quantify the performance improvement attributable to these 3D interfaces, analyzing their effects on both the anode and cathode sides is necessary. In this study, we fabricated an SOFC with asymmetric, a microscale prism-shaped anode/electrolyte interface and a planar electrolyte/cathode interface. This was achieved using an integrated approach involving ceramic micropatterning and subsequent electrospray deposition. The fabricated 3D cell achieved a 42.8% increase in peak power density (1.115 W cm-2) at 650 degrees C relative to a reference cell with planar interfaces on both sides of the electrolyte layer. It also exhibited reductions of 38.4% and 23.9% in area-specific ohmic and area-specific polarization resistance (0.053 and 0.162 Omega cm2), respectively. Additionally, under controlled gas partial pressure conditions for the anode and cathode, the effects of the asymmetric interfaces on the electrochemical performance of the cell were evaluated via advanced electrochemical impedance analysis. The three-dimensional (3D) structuring of interfaces in solid oxide fuel cells (SOFCs) is a valuable morphological approach that maximizes the reaction area and ion transfer pathways, enabling operation at lower temperatures.