用超高真空红外谱研究单晶TiO2(110)表面光催化机理

As a photocatalytic functional material with excellent performance, titanium dioxide (TiO2) is being applied more and more in fields as the new energy, environmental protection and so on, but the specific action mechanism of TiO2 in these reactions is still in debate. In this project, the rutile single crystal TiO2(110) stoichiometric surface as a model catalyst, the modified surfaces such as the oxygen vacancy surface, the N-doped surface and the nano-Au particle supported surface will be prepared by surface technology; The adsorption amount of probe molecules such as carbon monoxide (CO), nitric oxide (NO), formic acid (CHOOH) and methanol (CH3OH) is precisely controlled, and their adsorption site and adsorption state on the stoichiometric and modified surfaces are studied by using of the international advanced ultra-high vacuum infrared spectrum; Upon UV or sunlight irradiation, the chemical reaction of the molecules on their adsorption sites is studied to find the reaction conditions, the reaction site and reaction path of the probed molecules in the catalytic and photocatalytic reactions on the different surfaces; Combined with theoretical calculations, the catalytic and photocatalytic reaction mechanism is explored for the molecules on different surfaces. The implementation of this project will be helpful for our understanding on the reaction mechanism of photocatalysis of the TiO2(110) surface, and also play a positive role in further improving the catalytic efficiency of TiO2 in the applications.

作为性能优越的光催化功能材料，二氧化钛（TiO2）在新能源、环保等领域正得到越来越多的应用，但TiO2在不同光催化反应中的具体作用机理急需研究。本项目中，我们以金红石型单晶TiO2(110) 理想配比表面为模型催化剂，通过表面技术制备氧空位表面、N掺杂表面、纳米Au颗粒负载表面等TiO2(110)各改性表面；精确控制一氧化碳、一氧化氮、甲酸和甲醇等探针分子的吸附量，利用国际先进的超高真空红外谱技术研究各分子在TiO2(110)理想配比及各改性表面的吸附位置及吸附状态；借助于紫外或日光的辐照，研究各表面不同吸附位置的各分子的氧化或还原反应，寻找各分子在不同表面催化及光催化反应的反应位置和反应路径；结合理论计算，探索各分子在不同表面催化及光催化反应机理。本项目的实施，有助于我们对TiO2(110)表面光催化反应机理的认识，同时对如何进一步提高TiO2在应用中的催化效率也将起到积极的指导作用。

以二氧化钛（TiO2）为代表的过渡金属氧化物以其优越的催化和光催化性能，在新能源和环保等多个领域起到越来越多的作用。本项目中，我们以金红石型单晶TiO2(110)表面为主要的模型催化剂，并辅以锐钛矿型TiO2(110)表面、ZnO(10-10)表面和NiO薄膜，通过表面科学技术制备氧空位表面、富氧表面和纳米Au 颗粒负载表面等各改性表面；然后，控制一氧化碳、一氧化氮和二氧化碳等探针分子的吸附量，并利用国际先进的超高真空红外谱技术研究各分子在表面的吸附位置及吸附状态。我们获得了NO在TiO2(110）表面的反应规律，得到了分子在氧化物表面竞争吸附规律，利用NO在TiO2(110)表面的反应调控了纳米Au团簇的氧化态，发现了CO2在ZnO(10-10)表面的链式吸附及机理，阐明了缺陷态极化子参与分子吸附的两种方式等。本项目的成果，有助于我们对氧化物表面催化反应机理的认识。项目共发表文章6篇，待投稿文章数篇。培养博士生2名，硕士生3名，其中已毕业硕士生1名。项目已支出经费49.1万元，结余30.9万元，将用于本项目的后续研究。