New perspectives of Pt–CeO2 system: stabilization on MWCNTs for boosting activity and water‐resistance in CO oxidation at ambient temperatures

Abstract

The present study elucidates new perspectives regarding the Pt–CeO2 system for CO oxidation. The successful deposition of highly dispersed Pt–CeO2 species onto the surface of multiwalled carbon nanotubes (MWCNTs) led to the formation of abnormally active and water‐resistant catalysts. The catalysts were investigated by structural (XRD, TEM), spectral (XPS), and kinetic (TPR–CO+O2, TPR–CO, TPR–H2) methods. The application of TPR–CO+O2 revealed the remarkably high activity of all Pt–CeO2/MWCNTs catalysts at temperatures below 0 °C. The study of the catalysts at ambient temperature demonstrated high CO conversion in the presence of water vapor at a concentration of 100 ppm CO. The experimental findings suggest that active sites, comprising platinum structures stabilized directly on the surface of MWCNTs, play a pivotal role in the oxidation of CO under humid conditions. A dual–site approach was employed to develop a kinetic model that effectively describes the experimental data. This model provides valuable insights into the mechanism of wet CO oxidation.