Ferric oxide-supported Pt subnano clusters for preferential oxidation of CO in H₂-rich gas at room temperature

Pt single atoms and small clusters were dispersed on iron oxides by a facile coprecipitation method. These catalysts, with or without calcination at elevated temperatures, show excellent activity and selectivity for preferential oxidation of CO in the H₂-rich gas. They can completely remove CO from H₂-rich gas at a wide temperature range of 20-70 °C, which renders them suitable for low-temperature applications. The reaction followed a mixture of competitive mechanism and a noncompetitive/redox mechanism. The weakened CO adsorption on small Pt clusters and atoms makes the competitive adsorption of O₂ feasible, which ensures a high activity of Pt/Fe catalysts, even calcined at elevated temperature.