Regulating the interfacial active sites in Pt/ZrO2 catalysts for efficient styrene oxidation

Developing efficient and durable catalysts for catalytic oxidation reaction remains a major challenge. In this work, we found that Pt/ZrO 2 catalyst demonstrated superior performance compared to Pt sites supported on other oxides (e.g., Pt/Al 2 O 3 , Pt/CeO 2 and Pt/Ce 0.6 Zr 0.4 O 2 ) for styrene combustion. To further understand the active sites in Pt/ZrO 2 catalyst, a series of Pt/ZrO 2 catalysts were synthesized via wet impregnation and calcined at different temperatures (250, 300, 500, 700 and 900 °C). Among them, Pt/ZrO 2 -300 (calcined at 300 °C) exhibited the superior performance for styrene combustion. Comprehensive characterizations revealed that the calcination temperature critically influences the geometric and electronic structures of Pt sites, thus governing the generation of Pt σ+ -ZrO 2 interfacial active sites. A moderate calcination temperature is crucial for forming such interfacial active sites, lower temperatures fail to generate them, while higher temperatures result in nanoparticle sintering and a consequent diminution of these sites. Pt/ZrO 2 -300 features small Pt nanoparticles and a higher concentration of active Pt σ+ species, beneficial for the generation of interfacial active sites. In addition, our findings demonstrate that the superior performance of Pt/ZrO 2 -300 in styrene adsorption and oxygen activation stems from its abundant Pt σ+ -ZrO 2 interfacial active sites. Therefore, this work provides valuable insights for the rational design of robust catalysts with interfacial active sites.