Pd负载型介孔ZrO2-TiO2复合材料的设计合成及其CO催化氧化性能研究

为了有效去除大气污染物中的CO，使用氧化还原法制备层状锰氧化物MnO_x-L，并用离子交换法制备了负载不同质量分数Fe的Fex/MnO_x-L催化剂.使用扫描电子显微镜（scanning electron microscope，SEM）、X射线衍射（X-ray diffraction，XRD）技术、比表面积测定（brunauer emmett teller，BET）、热重分析（thermogravimetric analysis，TGA）、氢气程序升温还原（hydrogen temperature-programmed reduction，H₂-TPR）、氧气程序升温脱附（oxygen temperature-programmed，O₂-TPD）、X射线光电子能谱（X-ray photoelectron spectroscopy，XPS）等技术表征催化剂形貌、结构及性能.层状锰氧化物MnO_x-L具有典型的八面体层状结构，Fe负载对催化剂结构影响不大，但对其理化性质产生了影响.Fe负载改变了催化剂的还原性及其表面的m（Fe²⁺）/m（Fe³⁺）和m（O_ads）/m（O_latt）比例，提高了样品的催化活性.在所有Fex/MnO_x-L样品中，Fe5/MnO_x-L具有最高的低温还原性、氧移动性，m（Fe²⁺）/m（Fe³⁺）及表面吸附氧最高.催化氧化CO反应中，Fe5/MnO_x-L具有最佳的催化活性（t₅₀=80℃和t₉₀=150℃），这与Fe和MnO_x-L载体之间的相互作用有关.

Pd loaded mesoporous ZrO2-TiO2 composite and its CO catalytic oxidation property

To effectively remove CO from atmospheric pollutants, the octahedral layered birnessites (MnO_x-L) was prepared by a redox method, and Fex/MnO_x-L samples with different mass fractions of Fe loading were prepared by ion exchange method. Physicochemical properties of the samples were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) technique, BET (specific surface area measurement), thermogravimetric analysis (TGA), hydrogen temperature programmed reduction (H₂-TPR), oxygen temperature-programmed desorption (O₂-TPD), X-ray photoelectron spectroscopy (XPS) techniques. MnO_x-L support was a typical octahedral birnessites structure. Fe loading did not affect the support structure, but influenced their physical and chemical properties. The reduction of the catalyst and the ratio of m(Fe²⁺)/m(Fe³⁺) and m(O_ads)/m(O_latt) on the surface changed, as well as the catalytic activity significantly improved after loading iron. Among Fex/MnO_x-L samples, Fe5/MnO_x-L showed the best reducibility, oxygen mobility, and the highest ratio of m(Fe²⁺)/m(Fe³⁺) and surface adsorption oxygen. Fe5/MnO_x-L showed the best catalytic activity (t₅₀=80℃ and t₉₀=150℃) for CO oxidation, related to the interaction between Fe species and MnO_x-L.