| 초록 |
Pd/CeO2 were known to be efficient catalysts for automobile exhaust purification systems, especially diesel oxidation. However, the diesel exhaust often undergoes harsh conditions, suffering from high temperature up to ~750 ˚C. These conditions cause the sintering of Pd nanoparticles, resulting in loss of the catalytic active sites. In addition, poison species, such as carbonate and sulfate, would be formed on the CeO2 surface during exhaust purification, severe deactivating catalyst. Hydrothermal (HT) treatment on the Pd/CeO2 affected the catalyst structure, resulting in enhanced catalytic activity and durability for CO oxidation. Interestingly, low temperature CO oxidation activity was considerably enhanced after HT treatment. Moreover, all CO molecules were successfully removed below 150 °C even in the presence of C3H6 or SO2. Also, promoting effects were well maintained for recyclability test, longer reaction time, and even for temperature fluctuation up to 850 °C. |
