铈基和镧基复合氧化物催化剂催化碳烟燃烧性能研究

文章采用浸渍法、水热合成法和共沉淀法制备了3种不同类型的碳烟催化剂:CeFeCo、La-Mn-O和BiCeO。通过对3种样品扫描电镜（SEM）、X射线衍射（XRD）、X射线电子能谱（XPS）和氢气程序升温还原（TPR）等表征结果进行比较分析，发现: La-Mn-O样品中吸附氧的占比量最大；CeFeCo样品中的金属离子含量最多，且Ce3+含量大于BiCeO样品。在氢气程序升温还原中，可以观察到CeFeCo具有最低温的还原峰，在283 ℃左右。最后通过程序升温氧化反应系统对3个样品进行活性评估，在紧密接触情况下CeFeCo、La-Mn-O和BiCeO样品催化50%碳烟氧化所需的温度，即T₅₀分别为329、355 和374 ℃，与碳烟燃烧的空白组相比，T₅₀分别降低了265、239和220 ℃。这表明3种催化剂均成功制备并且具有良好的催化碳烟燃烧性能，特别是CeFeCo催化剂表现出的低温催化燃烧性能最好。

Study on the Catalytic Soot Combustion Properties of Cerium- and Lanthanum-Based Composite Oxide Catalysts

Three different types of carbon soot catalysts, CeFeCo, La-Mn-O and BiCeO, were prepared by impregnation, hydrothermal synthesis and co-precipitation methods. By comparing and analyzing the characterization results of the three samples, such as scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and H₂-temperature programmed reduction (TPR), it can be found that La-Mn-O sample has the largest proportion of chemisorbed oxygen, CeFeCo sample has the largest metal ion content, and Ce3+ content is higher than BiCeO sample. It can be found that CeFeCo has the lowest reduction peak at about 283 ℃ in the H₂-TPR. Finally, the activities of the three samples were evaluated by a temperature-programmed oxidation reaction system. The temperatures required to catalyze the oxidation of 50% soot for CeFeCo, La-Mn-O and BiCeO samples in tight contact were 329, 355 and 374 ℃, respectively, which were reduced by 265, 239 and 220 ℃, compared with the blank group. This indicates that all three catalysts were successfully prepared and had good catalytic soot combustion performance, and especially the CeFeCo catalyst exhibited the best low-temperature catalytic combustion performance.