High-entropy fluorite oxide supported Pt catalysts for catalytic ammonia combustion at 1200 °C

High-temperature catalytic ammonia combustion (HT-CAC) is a promising strategy for the clean and efficient utilization of energy carried by green NH₃ fuels. A key challenge lies in developing catalysts that offer high ammonia oxidation activity, excellent thermal stability, and high N₂ selectivity. In this study, we synthesized a high-entropy fluorite oxide aerogel (HEFOA) via supercritical drying. The enhanced chemical disorder results in a higher specific surface area and improved thermal resistance compared to its low-entropy counterpart (LEFOA). Incorporating Pt through a one-pot method yielded Pt@HEFOA, which demonstrated good catalytic activity and long-term stability during a 50-hour HT-CAC test at 1200 °C. This work opens new avenues for designing robust ammonia combustion catalysts that remain effective at extreme temperatures, which can contribute to the development of a sustainable NH₃-based hydrogen energy cycle.