Enhancing Stability and Activity of Fe‐based Catalysts for Propane Dehydrogenation via Anchoring Isolated Fe‐Cl Sites

The eco‐friendly features and desirable catalytic activities of Fe‐based catalysts make them highly promising for propane dehydrogenation (PDH). However, simultaneously improving their stability and activity remains a challenge. Here, we present a strategy to address these issues synergistically by anchoring single‐atom Fe−Cl sites in Al3+ vacancies of Al2O3. As‐synthesized Fe‐Cl/Al2O3 catalyst exhibited greater charge transfer between Cl and Fe than that between O and Fe in conventionally impregnated single‐atom Fe/Al2O3 catalysts, resulting in higher effective magnetic moments for Fe‐Cl/Al2O3 compared to Fe/Al2O3. When tested in PDH, the durability of Fe‐Cl/Al2O3 exceptionally lasted for 250 h under continuous regeneration conditions comprising 60% C3H8 (40% N2), followed by pure C3H8 at 600 °C while maintaining a high propylene space‐time yield of 1.2 molC3H6 gFe‐1 h‐1, surpassing the performance of previously developed Fe‐based PDH catalysts. We demonstrate that anchoring Fe−Cl into Al3+ vacancies simultaneously enhances stability and suppresses coke formation, owing to unique atomically dispersed Fe−Cl active structures. Compared with Fe/Al2O3 catalysts, charge transfer between Cl and Fe active centers reduces the activation energy barrier for C−H activation during C3H8 dehydrogenation, thereby improving catalytic activity; this may be related to their spin state as observed in in‐situ X‐ray emission spectroscopy studies during PDH.