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利用X射线衍射、N2吸附等温线、X射线光电子能谱、X射线吸收谱、H2-程序升温还原、甲基橙选择化学吸附和等电点测定等方法研究了共沉淀方法制备的一系列Cex Ti1-x O2复合氧化物的结构. 成功发展了甲基橙选择化学吸附和等电点方法研究Cex Ti1-x O2复合氧化物的最外层表面结构, 并定义了“等价CeO2表面覆盖度”来描述Cex Ti1-x O2复合氧化物的最外层表面结构. Cex Ti1-x O2复合氧化物 (x ≥ 0.7)形成立方萤石相固溶体, Ce0.3Ti0.7O2表现出纯的单斜相, 而其它复合氧化物表现出混合相. CexTi1-x O2复合氧化物最外层表面结构的演变行为不同于其体相结构. Ce0.7Ti0.3O2立方萤石相固溶体最外层表面已经部分形成了单斜相Ce0.3Ti0.7O2, 随Ce含量的降低, 单斜相Ce0.3Ti0.7O2从最外层表面向体相生长. Cex Ti1-x O2复合氧化物立方萤石相固溶体和单斜相Ce0.3Ti0.7O2分别在相对较低和较高的温度表现出好的还原性能. 上述结果提供了全面和深层次的Cex Ti1-x O2复合氧化物结构信息.
X-ray diffraction, N2 adsorption isotherm, X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, H2-temperature programmed reduction, methyl orange selective chemical adsorption and isoelectric point determination of a series of coprecipitation methods Cex Structure of Ti1-x O2 composite oxide The methyl orange selective chemical adsorption and isoelectric point method were successfully developed to study the surface structure of the outermost layer of Cex Ti1-x O2 composite oxide and to define the equivalent CeO2 surface coverage Degree "to describe the outermost surface structure of the Cex Ti1-x O2 composite oxide Cex Ti1-x O2 complex oxide (x ≥ 0.7) forms a cubic fluorite phase solid solution, Ce0.3Ti0.7O2 exhibits pure mono While the other composite oxides exhibit a mixed phase.The evolution behavior of the outermost surface structure of CexTi1-xO2 composite oxide is different from that of the bulk phase Ce0.7Ti0.3O2 The cubic fluorite phase solid solution has the highest surface area The monoclinic Ce0.3Ti0.7O2 is partially formed and the monoclinic Ce0.3Ti0.7O2 grows from the outermost surface to the bulk as the Ce content decreases.The CefTi1-xO2 composite oxide cubic fluorite solid solution and Monoclinic Ce0.3Ti0.7O2 at relatively low and high temperatures, respectively Exhibit good performance reduction. These results provide a comprehensive and in-depth Cex Ti1-x O2 complex oxide structure information.