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用柠檬酸法制备了铈锆固溶体负载不同量LaCoO3的催化剂。用热重法测试了催化剂样品对碳烟的催化活性。采用程序升温还原法(H2-TPR)、BET、X-射线衍射仪(XRD)和X-射线光电子能谱仪(XPS)对催化剂进行了测试。结果表明,铈锆固溶体表面形成了稳定的LaCoO3钙钛矿相结构;负载量为30%LaCoO3的催化剂具有最高的催化活性,起燃温度降到530℃;催化剂的催化活性与催化剂还原峰强度以及催化剂表面氧物种OII的含量紧密相关。
Cerium zirconium solid solution was prepared by citric acid catalyst loaded with different amounts of LaCoO3. The catalytic activity of the catalyst sample on soot was tested by thermogravimetry. The catalysts were tested by temperature-programmed reduction (H2-TPR), BET, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) The results show that the stable LaCoO3 perovskite phase is formed on the surface of cerium-zirconium solid solution. The catalyst with the highest loading of 30% LaCoO3 has the highest catalytic activity and the light-off temperature drops to 530 ℃. The catalytic activity of the catalyst decreases with the reduction peak intensity of the catalyst, The content of oxygen species OII on the catalyst surface is closely related.