中文摘要：

利用葡萄糖水热法制备了两类Co修饰Au@CeO_2核壳结构纳米催化材料：一类为保持Au@CeO_2的量不变,改变Co的加入量,该类样品命名为m%Co-Au@CeO_2（m%为样品中Co的摩尔分数）;另一类是保持金含量不变,Co/Ce摩尔比改变,该类样品命名为2%Au@CeO_2-Co_3O_4X（2%为金的质量分数,X=nCo/nCe×100）。利用XRD、SEM、TEM等手段,表征了两类核壳结构样品的物相结构及表面性质,并研究了样品的一氧化碳低温氧化催化性能。结果表明,CeO_2和Co_3O_4共存于样品m%Co-Au@CeO_2中,两种氧化物之间的相互作用能够抑制彼此晶粒的生长,当Co含量为40%时,样品的一氧化碳低温氧化活性最高,但仍低于未修饰样品,这说明仅靠增加Co的用量来改变材料的催化活性,并不能达到理想的效果。而在Au含量不变的条件下,通过改变Co/Ce比可使材料的催化性能得到改善,其中2%Au@CeO_2-Co_3O_460的粒径最小,催化活性最好。

英文摘要：

Two types of Co modified Au@CeO_2 core-shell structure nano catalytic material for carbon monoxide oxidation at low temperature are prepared by glucose hydrothermal method.One is named as m%Co-Au@CeO_2,in which the amount of Au@CeO_2 kept constant and m%is the molar percent of Co.The other is named as 2%Au@CeO_2-Co_3O_4 X,in which 2% is the mass percent of Au and X is the molar ratio of Co/Ce.All the samples are characterized by XRD,TEM and SEM methods and the catalytic activity for carbon monoxide oxidation is also tested.The results proved that CeO2 and Co_3O_4 coexist in m%Co-Au@CeO_2 and the interaction between them can prohibit the particles growth with each other.When the content of Co reaches 40%,the catalytic activity is the highest but still lower than that of pure Au@CeO_2,which indicates that the increase of Co content can＇t improve its activity.However,when the mass percent of Au is kept constant,the change of Co/Ce molar ratio can improve the catalytic activity.The particle size of 2%Au@CeO_2-Co_3O_4 60 is the smallest while its catalytic activity is the highest.