金纳米团簇/氧化物上炔烃活化的表界面调控性理论研究

The investigations of the adsorption and activation alkynes on surface and interface of gold cluster/oxide have important theoretical and practical significance in synthetic chemistry and medicinal chemistry. There are two key issues which need to be further investigated: The first one is the regulation of carrier oxide on the structures and properties of gold clusters and gold cluster-oxide interface, and the adsorption of alkynes on surface and interface of gold cluster/oxide. How to regulate adsorption of alkyne on Au/oxide to improve the catalytic activity and selectivity of alkyne activation reactions catalyzed by Au/oxide though the variation of the structure of gold-oxide interface and interaction between gold clusters and oxide. In the present proposal, we will investigate systematically the regulation roles of various crystal face, step surface, and oxygen vacancy of carrier oxide on the structures and properties of gold clusters and gold cluster-oxide interface, and the adsorption of alkynes on surface and interface of gold cluster/oxide. The transition metals Au, Ag, Cu, Ni, Pd, and Pt are used to dope the gold clusters and oxide surface to regulate the surface and interface of the gold nanocluster-oxide. The adsorption of alkyne on doping gold cluster/oxide and gold cluster/doping oxide are investigated to clarify the regulation role of doping metal on the gold cluster-oxide interaction. Accordingly, the electronic mechanisms of catalytic activity and selectivity of alkyne activation reactions are linked with the electronic transfer between gold clusters and oxide. Furthermore, the regulation behaviors of adsorption and activation of alkynes on the surface and interface of gold cluster/oxide are illuminated. This study can provide an important foundation for the development of catalysts with highly catalytic activity and selectivity.

研究金团簇/氧化物表界面上炔烃吸附活化在合成化学和药物化学中有重要理论与实践意义。炔烃在金团簇/氧化物表界面上活化有两个重要问题需要深入研究：氧化物载体对金团簇以及金团簇-氧化物界面的结构与性质对炔烃吸附活化的调控作用；如何通过改变金-氧化物界面结构和相互作用来调控金团簇/氧化物对炔烃的吸附活化，提高金团簇/氧化物对炔烃活化反应的催化活性和选择性。本项目拟用密度泛函理论与溶剂化模型方法，选取炔烃活化反应常见炔烃的模型物，系统研究氧化物载体的不同晶面、台阶面、氧空位等对金团簇和金团簇-氧化物界面结构以及炔烃吸附活化的调控作用；通过掺杂方式对金团簇-氧化物表界面进行调控，计算炔烃模型物在掺杂金团簇/氧化物和金团簇/掺杂氧化物表界面上吸附活化。阐明金团簇-氧化物间电子传递对催化活性和选择性影响的电子机制，明确金团簇/氧化物上炔烃吸附活化的表界面调控行为，为设计高活性和高选择性催化剂提供理论依据。

本项目研究了Au团簇以及Au/氧化物表界面活化吸附炔烃活化性质调控以及功能炔烃在表界面上反应机理和产物选择性，建立了表界面反应活性位点结构与反应活性关系：(1)用PBE和DFT+U等理论方法研究了气相Au2~20团簇和Au2~20、金纳米棒在TiO2(110)和CeO2(111)面上稳定结构，表面电荷对金团簇结构影响较大，Au3-10团簇在气相中以平面结构为主，而在TiO2和CeO2表面以立体结构较为稳定，分析了不同载体对表面团簇电荷分布影响，从而阐明载体对表面界面金原子性质调控。(2)用PBE泛函和DFT+U系统研究了乙炔和取代炔烃在气相Au2~20团簇和Au2~20、金纳米棒在TiO2(110)和CeO2(111)面的表面和界面金原子上的吸附于活化，阐明了载体对炔烃吸附和活化的构效关系。(3)采用第一性原理方法研究了功能化炔烃在Au38，掺杂Au38团簇，掺杂的Au表面和Au3-10/CeO2上的反应机理，阐明了氧化物和掺杂对金团簇催化活性的调控作用。(4)研究了Au、Pt、Rh、Ru等金属对Pd，Pt纳米金属团簇掺杂对催化反应活性的影响，将实验研究与理论研究相结合阐明了掺杂金属对催化反应机理的调控作用。研究成果有助于进一步了解催化剂活性起源和产物选择性控制因素，为寻找和设计新高效率和高选择性催化剂提供理论依据。.在本项目资助下，该课题密切相关的研究论文13篇，相关工作分别发表在ACS Catalysis (1篇)、ChemCatChem(2篇)、J Phys. Chem. C, PCCP等国际权威刊物上，影响因子大于3的12篇，培养硕士研究生3名，并邀请美国阿肯色大学医学院Prof. Hong-yu Li来校交流指导。