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/CeO₂ catalysts for soot oxidation have been reported. Herein, Ag/La-CeO₂ catalysts with different La contents are synthesized and compared to analyze the effect of La. Hydrogen temperature programmed reduction analysis confirms that the reducibility increases with an increase in the La content in La-CeO₂. X-ray photoelectron spectroscopy and Raman analysis confirm an increase of oxygen vacancies with La doping. Accordingly, the soot oxidation performances estimated by temperature programmed oxidation experiments increase with La doping. However, the catalytic activity of Ag/La-CeO₂ exhibits a volcano trend. When an appropriate amount of La is incorporated in Ag/CeO₂, peroxide generation and reducibility improve, thereby enhancing the soot oxidation performance. Conversely, the catalytic activities gradually decrease with excess La-doping. Scanning transmission electron microscopy analysis and density functional theory calculations confirm that excess amounts of La induce the sintering of Ag particles, which lead to the degradation of peroxide generation and reducibility of the catalysts. Consequently, an optimal amount of La incorporation on Ag/La-CeO₂ results in the best soot oxidation performance.

由于加强了对车辆排放的法规，使用柴油机微粒过滤器技术来减少微粒物质的排放已经引起了广泛的关注。为了实现颗粒物的低温氧化，已经报道了许多用于烟灰氧化的Ag / CeO ₂催化剂的研究。本文中，合成了不同La含量的Ag / La-CeO ₂催化剂，并进行了比较，以分析La的影响。氢程序升温还原分析证实，随着La-CeO _2中La含量的增加，还原性增加。。X射线光电子能谱和拉曼分析证实了La掺杂会增加氧空位。因此，通过温度编程的氧化实验估计的烟灰氧化性能随La掺杂而增加。但是，Ag / La-CeO ₂的催化活性表现出火山的趋势。当在Ag / CeO _2中掺入适量的La时，过氧化物的产生和还原性得到改善，从而提高了烟灰的氧化性能。相反，随着过量的La掺杂，催化活性逐渐降低。扫描透射电子显微镜分析和密度泛函理论计算证实，过量的La引起Ag颗粒的烧结，这导致过氧化物生成的降解和催化剂的还原性。因此，在Ag / La-CeO ₂上掺入的La的最佳量导致最佳的烟so氧化性能。