Temperature‐Dependent Dynamics of Superoxide and Peroxide Anions in Hydrocarbon Catalytic Oxidation Over Single‐Atom Pt Catalysts

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ABSTRACT Understanding the properties of reactive oxygen species (ROS) is crucial for efficient oxidation catalyst design, yet their dynamics during oxidative reactions are still unclear. Herein, using a CeZrO 2 ‐supported single‐atom Pt catalyst (Pt SA /CeZrO 2 ), we studied temperature‐dependent behaviors of superoxide (O 2 •− ) and peroxide (O 2 2− ) anions and how multiple ROS are involved in the catalytic oxidation of mixed hydrocarbons. We show that O 2 •− species, having an unpaired electron and a Pt‐O‐O structure, accounts for surface reactivity at lower temperatures, which is critical to toluene ring‐opening below 200°C. At higher temperatures (200°C–450°C), O 2 •− desorbs, while the O 2 2− anion, anchored by an oxygen vacancy (Vo) in the form of Pt‐O‐O@Vo, exhibits high stability and activity, promoting initial propane activation. Through the “relay” cooperation of O 2 •− and O 2 2− species, the Pt SA /CeZrO 2 (Pt loading of 0.4 g Pt /L) achieves complete removal of mixed toluene and propane at 450°C, 150°C lower than on a commercial high‐Pt loading Pt NP /CeZrO 2 catalyst (0.9 gPt/L). Our study advances the understanding of the dynamics and synergism of multiple ROS in mixed hydrocarbon oxidation process and paves the way for the development of next‐generation catalysts suited for a broad operational temperature window.

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