采用共沉淀法制备了系列Ce0.5+xZr0.4-xLa0.1O2-Al2O3催化剂,其中0≤x≤0.4且Ce0.5+xZr0.4-xLa0.1O2与Al2O3的质量比为1:1.考察了该系列催化剂对柴油车排放碳烟的催化燃烧性能,并用低温N2吸附-脱附、X射线衍射(XRD)、X射线光电子能谱(XPS)、氢气程序升温还原(H2-TPR)和氧气程序升温脱附(O2-TPD)等手段对催化剂进行了表征.研究结果表明该系列催化剂均形成了具有立方萤石结构的固溶体.当x=0.2时,Ce3+离子在催化剂表面有一定的富集,此时催化剂具有最大的β氧脱附峰和最好的表面还原性能,同时具有良好的催化碳烟氧化活性,碳烟在该催化剂的起燃温度为360℃,具有较好的应用前景.%Ce0.5+x Zr0.4-x La0.1O2-Al2O3 catalysts were prepared by co-precipitation, where 0≤x≤0.4 and the mass ratio of Ce0.5+xZr0.4-xLa0.1O2∶Al2O3 was 1∶1. The catalytic activities of these catalysts for the catalytic combustion of diesel soot were investigated. The catalysts were further characterized by low temperature nitrogen adsorption-desorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), H2-temperature-programmed reduction (H2-TPR), and O2-temperature-programmed desorption (O2-TPD). The results showed that all the catalysts formed solid solutions with a fluorite-like structure. When x=0.2, the Ce3+ ions were partly rich on the surface of the catalyst. The catalyst was easily reduced by H2 and the desorption peak area of theβ oxygen species was the largest. The light-off temperature was 360 ℃ for the catalytic combustion of diesel soot over the catalyst suggesting good catalytic activity and potential application in diesel soot catalytic combustion.
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