金属与CeO2、TiO2相互作用的研究

用浸渍法制备了一系列以CeO2、TiO2为载体的催化剂，在载体上分别引入Ca和Pt、Ni并且对这些催化剂进行了XPS、XRD、TPR表征。考察了Pt、Ni对CeO2、TiO2体系还原性能的影响。结果表明，Pt、Ni的加入能使表面Ca/Ce,Ca/Ti原子比显著增加，Ca与载体之间存在强相互作用，而且Pt、Ni的加入能够增强这种相互作用。

Study of the interaction between metal and CeO2 as well as TiO2

A series of catalysts were prepared by the conventional impregnation method using cerium dioxide and titania as supports.Then calcium,platinum or nickel was added to the supports.These catalysts were characterized by XPS,XRD and TPR.The effects of platinum,nickel on the reducibility of catalysts Ca/CeO2,Ca/TiO2 were investigated.The XPS results indicate that these two metals can lead to the surface Ca/Ce or Ca/Ti atom ratio rising smoothly.To the system Ca/CeO2,the effect of nickel is more remarkable than platinum.CaO and TiO2 formed a perovskite of orthorhombic structure by impregnating original materials.CaTiO 3 phase was detected by XRD.It indicates that during the impregnation and calcinations steps the above interaction proceeds.In contrast,the effect of platinum on the surface Ca/Ti ratio is more remarkable that nickel to the system Ca/TiO2.The formation of solid solution occurs during the impregnation of Ca to CeO2.It is likely that different components of the sample create a synergistic effect.Strong metal support interaction(SMSI) exists between calcium and the supports.The interation is increased by platinum and nickel.In addition,platinum,nickel and supports have also strong interaction.Calcium makes platinum and nickel better disperse on the surface of the supports.