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采用共沉淀法制备了SnO_2-CeO_2复合金属氧化物催化剂,通过XRD、TEM、H_2-TPR、CO-TPR等表征手段对催化剂结构和氧化还原性能进行了研究,并考察其CO催化氧化性能。与SnO_2和CeO_2催化剂相比,SnO_2-CeO_2固溶体催化剂具有较小的晶粒尺寸和较大的比表面积。另外,H_2-TPR和CO-TPR结果表明,在H_2和CO的还原气氛下,由于Sn~(4+)+2Ce~(3+)Sn~(2+)+2Ce~(4+)氧化还原平衡的存在,SnO_2-CeO_2复合金属氧化物催化剂表面的Sn~(4+)氧化能力得到大幅度增强。其中,Sn_(0.7)Ce_(0.3)O_2催化剂由于具有最大的比表面积和最强的表面Sn~(4+)氧化能力,从而表现出了最佳的CO催化氧化性能。
The coprecipitation method was used to prepare SnO_2-CeO_2 composite metal oxide catalysts. The structure and redox properties of the catalysts were characterized by XRD, TEM, H_2-TPR and CO-TPR. The catalytic properties of the catalysts were also investigated. Compared with SnO_2 and CeO_2 catalysts, the SnO_2-CeO_2 solid solution catalyst has smaller grain size and larger specific surface area. In addition, the results of H 2 -TPR and CO-TPR show that due to the oxidation of Sn ~ (4 +) + 2Ce ~ (3+) Sn ~ (2 +) + 2Ce ~ (4+) under the reducing atmosphere of H_2 and CO, In the presence of reduction and balance, the Sn 4+ oxidation ability of SnO 2 -CeO 2 composite metal oxide catalyst is greatly enhanced. Among them, Sn_ (0.7) Ce_ (0.3) O_2 catalyst exhibited the best CO catalytic oxidation performance due to its maximum specific surface area and the strongest Sn 4+ oxidation ability.