金属单原子负载钙钛矿YbMnO3铁电体纳米结构低温CO氧化机制研究

本项目针对贵金属复合催化剂对CO催化能效低、成本高的缺点，拟利用过渡金属单原子(SA)的高催化活性，YbMnO3钙钛矿铁电体的自发极化特性以及温度和化学稳定的特点，构筑SA/YbMnO3复合CO热催化体系。考察不同暴露晶面YbMnO3纳米结构、表面缺陷、SA类型及负载量对CO催化性能的影响，通过分析催化剂的物相结构与催化活性的构效关系，实现对复合体系中SA类型、负载量以及YbMnO3结构的调控；探究YbMnO3的铁电自发极化特性对SA/YbMnO3界面以及CO、O2和CO2分子吸附的影响；通过理论计算模拟YbMnO3载体与SA之间、载体体相与表面之间的电子传输以及铁电自发极化对表面CO吸附和O2活化的影响，从而揭示SA/YbMnO3复合催化剂对CO低温催化的耦合机制。该项目研究可为高效、稳定、经济的SA/钙钛矿铁电体复合催化剂的设计与制备开辟新的途径和提供理论支持。

By considering the issue of poor stability and low efficiency of noble metal-based catalysts for carbon monoxide oxidation, this project proposes the construction of SA/YbMnO3 composite for CO thermo-catalytic due to the features of YbMnO3 ferroelectric materials with spontaneous polarization, temperature and chemical stability and the characteristics of single metal atom (SA) in low-cost and with excellent catalytic activity. The effects of the exposed crystal faces of YbMnO3 nanostructures, surface defects, SA types and the content loading on CO catalytic performance are investigated. By analyzing the phase structure-catalytic activity relationship of the composite catalyst, the SA type, loading amount and YbMnO3 structure in the composite catalysts would be controlled. The influence of YbMnO3 ferroelectric spontaneous polarization on the SA/YbMnO3 interface and the adsorption of CO, O2 and CO2 molecules on the catalyst surface are also investigated. Furthermore, the electronic transfer between the YbMnO3 and SA, also the bulk and surface of YbMnO3, and the ferroelectric spontaneous polarization on CO adsorption and O2 activation are simulated by theoretical calculation. Finally, the synergistic effect mechanism of SA/YbMnO3 composite on the catalytic oxidation of CO at low temperature will be revealed. The research of this project can contribute a new way and provide theoretical guidance for the design and preparation of efficient, stable and low cost SA/Perovskite ferroelectric composite for CO catalyst.