CO-CO2-MoO3(g)化学气相沉积强化碳化钼超微粉体结构与催化性能的协同调控

碳化钼具有类似铂族贵金属的电子结构和表面性质，在催化噻吩加氢脱硫方面表现出巨大潜能。针对传统制备方法碳化钼存在表层积碳、易团聚烧结、难以快速制取等关键问题，本项目拟以工业氧化钼为钼源，CO-CO2混合气体为还原碳化剂，提出一种基于CO-CO2-MoO3(g)化学气相沉积的高效制备方法。通过调控工业氧化钼本征属性和外在环境因素，首先研究原料的高温挥发行为，探索杂质组元的演变规律及其对三氧化钼挥发的影响机制。在此基础上，系统研究CO-CO2-MoO3(g)三元体系化学气相反应，获取其物相转变规律和形貌演变行为，揭示碳化钼超微粉体的成核长大机理以及多尺度结构调控机制。通过研究催化噻吩加氢脱硫反应前后碳化钼表面理化特征演变规律，建立表面结构与反应、传质间的内在联系，最终构筑碳化钼粉体结构与催化性能间的构效关系。研究结果可为高效规模制备催化性能优异的碳化钼超微粉体提供理论基础和新的思路。

Molybdenum carbide (Mo2C) has the similar catalytic performance as platinum group metals due to the unique electronic structure and surface property, which makes it widely used in the hydrodesulfurization of thiophene. In order to solve the problems of carbon deposition, reunion sintering, and hardly synthesis rapidly that existed in the traditional preparation method, a new route is proposed in the current project. Ultrafine Mo2C powder is prepared by the chemical vapor reaction of CO-CO2 mixed gases and vapor MoO3, in which industrial grade MoO3 is used as the raw material. By adjusting the intrinsic properties of industrial grade MoO3 and the external environmental factors, the project is first to study the vaporization behavior of raw material for the purpose of exploring the evolution law of impurities components and the formation mechanism of product. Afterward, the chemical vapor reaction behavior of the ternary system of CO-CO2-MoO3(g) is studied in order to illustrate the phase transformation law and reduction carburization mechanism, and the multi-scale structure regulation mechanism of ultrafine Mo2C powder is also obtained. Though the research of changes of physical and chemical properties of Mo2C powder before and after the catalytic reaction, the relationship between the structure and its catalytic performance for the hydrodesulfurization of thiophene is established. This results of the project will provide the theoretical basis and new route for the large-scale preparation of ultrafine Mo2C powder with high catalytic performance.