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用Ｘ射线光电子能谱（ＸＰＳ），对在不同干燥条件下制备的纳米晶体ＬａＣｏＯ３样品的组成、结构进行表征，利用曲线拟合分峰技术对催化剂样品中的各元素峰进行数据处理，并测定了各催化剂样品的ＣＯ氧化活性。结果表明，纳米晶ＬａＣｏＯ３表面存在两类氧种，即低结合能（５２８．１ｅＶ）的晶格氧（ｌａｔｉｃｅｏｘｙｇｅｎ）和高结合能（５３１ｅＶ）的吸附氧（ａｄｓｏｒｂｅｄｏｘｙｇｅｎ）；既有位于低结合能（７７９ｅＶ）的三价离子Ｃｏ（Ⅲ），又有位于高结合能（７８０．５ｅＶ）的二价离子Ｃｏ（Ⅱ）存在。由于干燥条件不同，它们的相对含量亦有较大差异，并对ＣＯ氧化活性产生较为明显的影响
The composition and structure of the nanocrystalline LaCoO3 samples prepared under different drying conditions were characterized by X-ray photoelectron spectroscopy (XPS). The curve fitting peak distribution technique was used to process the data of each element peak in the catalyst sample. The CO oxidation activity of each catalyst sample was measured. The results show that there are two kinds of oxygen species on the surface of nanocrystalline LaCoO3: laticeoxygen with low binding energy (528.1eV) and adsorbed oxygen with high binding energy (531eV) 779eV), and divalent Co (II) ions at high binding energy (780.5eV). Due to different drying conditions, their relative content is also quite different, and the CO oxidation activity had a more significant impact