【摘要】 采用沉积沉淀法合成了系列La2O3改性的Au/CeO2催化剂,并结合紫外可见漫反射光谱,X射线粉末衍射和透射电镜对其进行相关表征。La的引入改变了载体的结构缺陷,导致了体系中金属Au与载体的相互作用发生了不同程度的变化。La2O3的掺杂有利于提高载体CeO2中氧缺位浓度,在一定范围内有利于活性的提高。继续提高掺杂量,使得缺陷浓度过高时可能形成缺陷簇,改变了缺陷性质,反而使活性相对下降。La掺杂量为5at%的Au/CL5.0样品表现出最佳的WGS活性,300℃时CO转化率达到94.12%。更多还原

【Abstract】 For Au-ceria catalysts prepared by deposition-precipitation method,the catalytic performance of water gas shift reaction was studied with different La loadings.In the complete doping range,ceria retains with its cubic fluorite structures.XRD,HRTEM and UV-Vis-DRS,studies showed that La doping can improve the activity of Au-ceria catalyst by stabilizing ceria and modifying its morphology.In addition,the test of catalyst stability evaluation also proved that a better stability performance of Au-ceria catalyst can be realized by appropriate La doping.The Au/CL5.0 sample with 5 at% La doping showed the best performance in WGS reaction.更多还原