Pt and Ir supported on mixed Ce0.97Ru0.03O2 oxide as low-temperature CO oxidation catalysts

Pt and Ir catalysts (3% w/w) supported on Ce0.97Ru0.03O(2) were synthesized and successfully tested in a low temperature CO oxidation process. The CO oxidation was followed in-operation, by FTIR spectroscopy. The catalysts were characterized by SEM-EDS, HTEM, XRD, DRS UV-vis, XPS techniques and BET isotherms. It was found that Pt and Ir nanoparticles on Ce0.97Ru0.03O2 drastically improved the CO oxidation in comparison to CeO2, showing the best performance the Pt/ Ce0.97Ru0.03O(2) system. From the FTIR studies, a route for CO oxidation was proposed. The CO oxidation pathway in Ce0.97Ru0.03O(2) considers that CO was adsorbed at the Ce and Ru sites, while O-2 is adsorbed on the surface oxygen vacancies, being activated by nearby Ru species. Subsequently, the activated oxygen reacts with CO linked to Ce and Ru to produce CO2. Also, Pt and Ir promotes oxygen vacancies, increasing the activation-adsorption of O-2 and, consequently, the activity of the catalyst was improved.

Automated summary

The study found that Pt and Ir nanoparticles on Ce0.97Ru0.03O(2) significantly enhanced the activity of CO oxidation reaction, and proposed a CO oxidation pathway through FTIR spectroscopy.