采用ＸＰＳ等手段对ＬａＣｏＯ３－δ和Ｌａ１－ｘＳｒｘＣｏＯ３－δ纳米粒子进行了表征。结果显示，随ＬａＣｏＯ３－δ纳米粒子粒径的减小，一方面表面钴浓度增加，另一方面，表面ＣｏＯ键的离子性增强和表面氧空位浓度增加。此二者共同导致ＬａＣｏＯ３－δ对一氧化碳氧化的催化活性随其粒径减小而明显增大。ＬａＣｏＯ３－δ纳米粒子中镧被锶部分取代后，其表面结构发生了变化，并导致对一氧化碳氧化的催化活性显著提高 The LaCoO3-δand La1-xSrxCoO3-δnanoparticles were characterized by XPS and other methods. The results showed that with the decrease of the particle size of LaCoO3-δ, the surface cobalt concentration increased on the one hand, and the ionicity of the surface CoO bond and the surface oxygen vacancy concentration increased on the other hand. Together, these two factors lead to a marked increase in the catalytic activity of LaCoO3-δ for carbon monoxide oxidation as its particle size decreases. Lanthanum partially substituted by strontium in LaCoO3-δ nanoparticles changes its surface structure and leads to a marked increase in the catalytic activity for the oxidation of carbon monoxide