SBA-15 and Ce-SBA-15 molecular sieves were synthesized by microwave assistant sol-gel method with nonionic triblock co-polymer surfactant P123 as the template and tetraethyl orthosilicate as the silicon source, and were characterized by means of XRD, XPS and UV-Vis DRS. The results showed that ordered degree of Ce-SBA-15 molecular sieves was higher than that of SBA-15 molecular sieves and the cerium species existed in the forms of both Ce4+ and Ce3+. With CO oxidation as the model reaction, theinfluences of Ni promoter on the catalytic performances of the Pt-based catalysts supported on both the synthesized molecular sieves were investigated. The results showed that the activity of Pt/Ce-SBA-15 was better than that of Pt/SBA-15, and adding the Ni promoter further enhanced the catalyst activity. The complete oxidation of CO was realized at 160 ℃ over Pt-Ni/Ce-SBA-15 catalyst. To reach the same conversion, the reaction temperature has to be at 245 t in the case of Pt/SBA-15.%以三嵌段共聚物P123为模板剂、正硅酸乙酯为硅源,采用溶胶凝胶法,通过微波辅助加热实现了SBA - 15分子筛和Ce掺杂的Ce - SBA - 15分子筛的快速合成；通过XRD,XPS,UV - Vis DRS等手段对合成的分子筛进行了表征.表征结果显示,引入Ce得到的骨架掺杂Ce - SBA - 15分子筛的有序度较高,Ce以Ce3+和Ce4+两种形式存在于分子筛中.以合成的分子筛为载体制备负载型Pt催化剂,并以CO氧化为模型反应,考察了Ni助剂的添加对催化剂活性的影响.实验结果表明,以Ce - SBA - 15分子筛为载体的Pt催化剂比以SBA - 15分子筛为载体的Pt催化剂具有更高的CO氧化活性,且助剂Ni的添加能进一步提高催化剂的活性；Pt - Ni/Ce - SBA - 15催化剂在160℃可使CO完全转化,而Pt/SBA - 15催化剂在245℃时才能使CO完全转化.
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