Pt Nanoparticles Supported on the Graphitic CarbonNitride/CeO₂ Nanocomposite as a Catalyst for the Oxidationof Toluene

The Pt/CeO₂ catalyst is widely studied for the catalytic purification of volatile organic compounds (VOCs) due to its distinctive nanoscale features, including strong metal–support interaction (SMSI), abundance of oxygen vacancies, and excellent redox properties, and stability of CeO₂ nanomaterials. However, significant challenges remain, including the poisoning effect of water vapor and the excessive strengthening of the SMSI, which lead to an increased Pt valence state and loss of activity. In this work, we present a g-C₃N₄–CeO₂ nanocomposite-supported Pt catalyst (Pt/CN–CeO₂) for enhancing the catalytic oxidation of toluene. The electron-rich material, g-C₃N₄, interacts with CeO₂ to generate additional oxygen vacancies and donates electrons to Pt nanoparticles, facilitating the formation of active Pt⁰ species and improving the catalytic efficiency of toluene oxidation. The optimized Pt/CN–CeO₂ nanocomposite catalyst achieves a 90% toluene conversion at 203 °C, in contrast to 254 °C required for the conventional Pt/CeO₂ catalyst under the same conditions. In addition, the optimized Pt/CN–CeO₂ nanocomposite catalyst exhibits strong resistance to water poisoning and exceptional stability for toluene oxidation, consistently maintaining a toluene conversion rate above 99% at 210 °C for 50 h. These findings offer valuable insights into the design of advanced catalytic materials at the nanoscale and facilitate the application of Pt/CN–CeO₂ nanocomposite catalysts in environmental catalysis.