Effect of CeO₂ morphology on catalytic oxidation of ethylene oxide over Pt/CeO₂catalysts

Supported noble metal catalysts have been widely studied in the combustion of volatile organic pollutants due to their excellent catalytic performances. In this paper, Pt catalysts supported on three cerium oxides with different morphology (rod-shaped CeO2-NR, cubic CeO2-NC and octahedral CeO2-NO) were prepared by precipitation and deposition method, and the catalytic oxidation of ethylene oxide (EO) on the catalysts was studied. The results showed that EO oxidation activities by the three catalysts were ordered as Pt/CeO2-NR > Pt/CeO2-NO > Pt/CeO2-NC. XPS and Raman characterization results indicate that Pt/CeO2-NR has more active sites, appropriate oxygen vacancy content, and the strongest metal-support interaction. Furthermore, Pt/CeO2-NR has more uniformly dispersed Pt0 sites with stronger oxygen activation ability. As a result, Pt/CeO2-NR exhibits the most prominent EO catalytic oxidation performance with t50 and t90of 170 ℃and 190 ℃, respectively.