Thermal–electrochemical coupling via cascade catalysts in ammonia‐fueled solid oxide fuel cells

Abstract Direct ammonia solid oxide fuel cells (DA‐SOFCs) offer a promising route for efficient carbon‐free power generation. However, DA‐SOFCs still face inherent performance and durability challenges due to ammonia‐induced electrode corrosion. Here, built‐in catalysts are strategically arranged to enhance ammonia conversion, and their effects are comprehensively studied by combining experiment and multi‐physics simulations. The results demonstrate that built‐in catalysts shift ammonia decomposition from the anode to the catalyst, increasing ammonia conversion and anode temperature, thus achieving performance comparable to 0.75H 2 /0.25N 2 ‐fueled SOFCs even at low temperatures. A cascade catalysts configuration with stepwise catalytic activity markedly strengthens thermal coupling between the ammonia decomposition and the electro‐oxidation, reducing the maximum temperature difference by over 92%. Built‐in catalysts are simple to implement and achieve higher electrical efficiency than external catalysts. Moreover, they completely prevent ammonia–electrode contact over a wide temperature range, greatly improving durability. This study yields design guidance for developing high‐performance, durable DA‐SOFCs.