Large Area High-Performance Thin Film Solid Oxide Fuel Cell with Nanoscale Anode Functional Layer by Scalable Reactive Sputtering

For high-performance thin-film solid oxide cells (TF-SOCs), a nanostructured anode functional layer (n-AFL) that can prolong the triple-phase boundary (TPB) is crucial, particularly for low-temperature operation. However, the implementation of n-AFL (usually >1 µm in thickness) has critical issues in scale-up and productivity. Here, the study successfully demonstrates a large-area, high-performance TF-SOFC with an n-AFL fabricated via mass-production-compatible reactive magnetron sputtering. The cell with optimized n-AFL by adjusting crucial reactive-sputtering process parameters, i.e., oxygen partial pressure and sputtering power, shows superior performance compared to that of the cell without n-AFL: the reduction both in ohmic and anodic polarization resistances by 63% and 34%, respectively, and the improvement in maximum power density by 89% (0.705 W cm^-2 vs 1.333 W cm^-2) at 650 °C. When employed in large-scale cell (4 × 4 cm²), the TF-SOFC with n-AFL showed 19.4 W at 650 °C.