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采用共沉淀法制得了Ｃｅ４＋部分取代Ｌａ３＋的Ｌａ１－ｘＣｅｘＭｎＯ３钙钛矿型催化剂。实验结果表明，随Ｃｅ４＋取代量ｘ的增大，Ｌａ１－ｘＣｅｘＭｎＯ３催化剂越易被还原，其还原活化能逐渐降低。对于ＣＯ、ＣＨ４氧化反应其活性有一最大值，ＣＯ反应ｘ为０．４，ＣＨ４反应ｘ为０．２。这是由于随ｘ值的增大，催化剂晶格缺陷增多，晶格氧的化学势增大，以及ＣｅＯ２杂质相的协同作用的结果。在ＣＯ氧化和用Ｈ２还原中，发现两种氧种在反应中起作用，即低温时为吸附氧，高温时为晶格氧
The La1-xCexMnO3 perovskite catalyst with Ce4 + partial substitution of La3 + was prepared by coprecipitation method. The experimental results show that the La1-xCexMnO3 catalyst is more easily reduced with the increase of Ce4 + substitution amount, and the reduction activation energy decreases gradually. For CO, the CH4 oxidation reaction has a maximum value, the CO reaction x is 0.4 and the CH4 reaction x is 0.2. This is due to the increase of x value, the increase of the lattice defects of the catalyst, the increase of the chemical potential of the lattice oxygen, and the synergistic effect of the CeO2 impurity phase. In the oxidation of CO and the reduction with H2, two oxygen species are found to play a role in the reaction, that is, adsorbed oxygen at low temperature and lattice oxygen at high temperature