Effects of La incorporation in catalytic activity of Ag/La-CeO catalysts for soot oxidation.

Owing to strengthened regulations toward vehicle emissions, the use of diesel particulate filter technology to reduce particulate matter emissions has attracted significant attention. To achieve low temperature oxidation of particulate matter, numerous studies on Ag/CeO catalysts for soot oxidation have been reported. Herein, Ag/La-CeO catalysts with different La contents are synthesized and compared to analyze the effect of La.

CeO promoted Ag/TiO catalyst for soot oxidation with improved active oxygen generation and delivery abilities.

To evaluate the usability of TiO support for silver in soot oxidation, Ag/TiO and Ag/CeO catalysts were prepared and soot oxidation experiment was performed. The catalytic activity of silver was more enhanced on P25 and rutile than on anatase and CeO in tight contact, as evidenced from comparing the activities of supports and silver impregnated catalysts. The reasons for the difference in active metal enhancement were elucidated by various characterization methods (TEM, H TPR, and XPS), and it is verified that it resulted not from dispersion of silver but from oxidation ability.