Ce-Y-O固溶体及其PdO/Ce-Y-O催化剂的制备，表征和CH4氧化性能

采用柠檬酸溶胶－凝胶法制备了Ce-Y-O固溶体，并用XRD和Raman对Ce-Y-O固溶体的物相结构进行了表征，发现当n(Ce)/n(Ce Y)（摩尔比）≥0.6时，Ce-Y-O固溶体为面心立方结构，n(Ce)/n(Ce Y)≤0.5时为体心立方结构。固溶体的生成有利于提高氧化还原性能。Ce-Y-O固溶体担载PdO催化剂的CH4氧化活性表明，n(Ce)/n(Ce Y)对担载PdO催化剂的CH4氧化活性影响很大，当n(Ce)/n(Ce Y)＝0.8时催化剂活性最高，CH4转化率50％的温度为350℃，完全转化温度为600℃。

Characterization and Preparation of Ce-Y-O Solid Solutions and PdO/Ce-Y-O Catalysts for CH4 Oxidation

Ce-Y-O Solid Solution was prepared by citrate sol-gel method,and characterized by using XRD,Raman and TPR techniques.The structure of the solid solution depends on the Ce/(Ce+Y)ratio.When Ce/(Ce+Y)≥0.6,only face centered cubic phase is observed.When Ce/(Ce+Y)≤0.5,only body centered cubic phase is observed.The addition of Y atoms into CeO2 improves the reduction-oxidation behavior.Ce-Y-O-supported PdO catalysts show higher activity for CH4 oxidation than PdO/CeO2 and PdO/Y2O3 catalysts.The PdO/Ce0.8Y0.2O1.90 catalyst is the most active of all catalysts.