纳米Ce_xFe_(1-x)O_2固溶体的模板法制备及其乙醇水蒸气重整催化性能

Preparation of Nanoscale Ce_xFe_(1-x)O_2 Solid Solution Catalyst by the Template Method and Its Catalytic Properties for Ethanol Steam Reforming

以超高比表面炭材料为模板,硝酸盐为氧化物前体,通过改进的模板路线制备了具有较高比表面积的纳米CexFe1-xO2固溶体.采用X射线衍射、拉曼光谱、物理吸附和透射电镜对制备的样品进行了表征.结果表明,α-Fe2O3,CexFe1-xO2固溶体和CeO2的粒子尺寸为5～15nm,CeO2中部分Ce^4＋离子被Fe^3＋离子取代,从而形成了CexFe1-xO2固溶体.乙醇水蒸气重整反应结果显示,CexFe1-xO2固溶体比相应的α-Fe2O3和CeO2具有更高的催化活性和对氢气的选择性.

Nanoscale CexFe1-xO2 solid solutions with high surface area were prepared by a modified template route using an ultrahigh surface area carbon material as the template and nitrate as the oxide precursor. The resultant samples were characterized by XRD, N2 adsorption, Raman spectroscopy, and TEM. The results show that the particle sizes of α-Fe2O3, CexFe1-xO2 solid solutions, and CeO2 are 5-15 nm. Partial Ce^4＋ cations in the nanoscale CeO2 are substituted by Fe^3＋ cations, which results in the formation of CexFe1-xO2 solid solutions. The CexFe1-xO2 solid solutions have superior catalytic activity and selectivity for hydrogen in the ethanol steam reforming compared with the CeO2 and α-Fe2O3 catalysts.