铈铁复合氧化物纳米空心球的制备与催化性能

Synthesis and Catalytic Performance of Ce1-xFexO2 Composite Oxides Hollow Nanospheres

摘要:

用水热法制备的碳球(CS)作为模板,利用Ce₄₊与碳球表面的静电吸附以及高铁酸钾(K₂FeO₄)的强氧化性在碳球表面进行包覆,煅烧去除模板后得到铈铁复合氧化物(Ce_1-xFe_xO₂)纳米空心球。通过SEM、TEM、XRD、Raman、BET等手段对材料的结构进行了表征。结果表明纳米空心球平均直径约300 nm,壁厚约20~25 nm,Fe的含量对空心球的形貌有较大的影响。用CO催化氧化反应来测试材料的催化性能。结果表明Ce_0.95Fe_0.05O₂具有良好的催化性能,可以在297℃实现对CO的完全氧化,并且具有非常高的催化稳定性。

Abstract:

A series of Ce_1-xFe_xO₂(x=0, 0.05, 0.1, 0.15, 0.2) composite oxides hollow nanospheres were successfully synthesized using the template method. Carbon spheres prepared by hydrothermal method were used as the hard template. The coating was induced by the strong oxidizing K₂FeO₄, and the electrostatic adsorption between Ce₄₊ and CS. The catalysts were characterized by means of SEM, TEM, XRD, Raman and BET. The sizes and thicknesses of hollow nanospheres were about 300 nm on average and 20~25 nm, respectively. The ratio of Fe/Ce had a significant effect on the morphology of hollow spheres. Catalytic properties were tested by catalytic oxidation of CO. Ce_0.95Fe_0.05O₂ hollow nanospheres showed an enhanced catalytic performance that the total conversion of CO was 297_oC, and also showed high stability against high temperature.