Enhanced Catalytic Ozonation for Eliminating CHSH via Graphene-Supported Positively Charged Atomic Pt Undergoing Pt/Pt Redox Cycle.

Constructing catalysts with electronic metal-support interaction (EMSI) is promising for catalytic reactions. Herein, graphene-supported positively charged (Pt/Pt) atomically dispersed Pt catalysts (AD-Pt-G) with PtC ( = 1, 2, and 4)-based EMSI coordination structures are achieved for boosting the catalytic ozonation for odorous CHSH removal. A CHSH removal efficiency of 91.5% can be obtained during catalytic ozonation using optimum 0.5AD-Pt-G within 12 h under a gas hourly space velocity of 60,000 mL h g, whereas that of pure graphene is 40.4%. Proton transfer reaction time-of-flight mass spectrometry, diffuse reflectance infrared Fourier transform spectroscopy/Raman, and electron spin resonance verify that the PtC coordination structure with atomic Pt sites on AD-Pt-G can activate O to generate peroxide species (*O) for partial oxidation of CHSH during the adsorption period and trigger O into surface atomic oxygen (*O), *O, and superoxide radicals (·O) to accomplish a stable, high-efficiency, and deeper oxidation of CHSH during the catalytic ozonation stage. Moreover, the results of XPS and DFT calculation imply the occurrence of Pt → Pt → Pt recirculation on PtC for AD-Pt-G to maintain the continuous catalytic ozonation for 12 h, i.e., Pt species devote electrons in 5d-orbitals to activate O, while Pt species can be reduced back to Pt via capturing electrons from CHSH. This study can provide novel insights into the development of atomically dispersed Pt catalysts with a strong EMSI effect to realize excellent catalytic ozonation for air purification.