Photothermal Catalytic Dry Reforming of Methane With 1000‐Hour Stability via Redox Shuttle of Metal Vanadate

ABSTRACT Photothermal catalytic dry reforming of methane (DRM) mediated by lattice oxygen (O l ) is promising for converting two major greenhouse gases into syngas. However, conventional oxide supports possess strong metal–oxygen bonds that restrict O l migration, compromising stability, typically less than 200 h. Herein, we design a Rh/Mg 2 V 1.33 O 4 catalyst with Rh δ + ─O v ─V n + interfacial sites ( n = 3 or 4). The defective spinel vanadate support exhibits quasi‐metallic properties, enabling efficient solar harvesting and photothermal conversion. Under 4 W cm −2 light irradiation without external heating, the redox flexibility of V species enables an interfacial redox shuttle (Rh δ + ─O v ─V n + ⇌ Rh δ + ─O l ─V ( n +1)+ ), which endows the catalyst with effective O l migration and regeneration ability in the DRM reaction. This property steers the reaction along a coking‐resistant CH 3 O* pathway and guarantees structural stability. As a result, the catalyst delivers long‐term stability for 1000 h, outperforming state‐of‐the‐art photothermal catalysts. It also achieves high syngas generation rates of 16.1 and 18.6 mol g Rh −1 h −1 for H 2 and CO, respectively, along with a light‐to‐chemical energy efficiency of ∼20.9%. This work establishes quasi‐metallic, redox‐active vanadate supports as a transformative platform for durable O l ‐mediated photothermal catalysis.