甲醛是一类典型的挥发性有机污染物，严重威胁人类健康。催化氧化法能够高效地将甲醛完全转化为二氧化碳和水，因而引起研究者的极大关注。Ag-CeOx催化剂因兼具低成本和较高活性等特点，被广泛应用在催化氧化甲醛反应中。然而由于缺乏高效、灵敏的原位表征技术，致使Ag与CeO2之间的界面化学特性及该界面在催化氧化甲醛反应过程中的作用尚不明确。本项目以一氧化碳氧化为模式反应，应用原位局域表面等离子体共振-质谱联用技术研究CeO2/Ag催化剂表界面特性及其在该反应过程中的作用；随后，将该技术与原位红外漫反射和理论计算相结合，应用于更加复杂的催化氧化甲醛反应研究中，建立CeO2/Ag表界面化学特性与甲醛氧化过程中各个重要中间反应步骤的联系。本项目有助于加深对催化氧化甲醛反应机理的理解，并指导CeO2/Ag催化剂的理性优化以进一步提升其反应活性。

Formaldehyde is one of typical Volatile Organic Compounds (VOCs), which threatens human health. Catalytic oxidation is an effective way to convert formaldehyde into carbon dioxide and water, therefore attracts lots of attention. Due to low costs and relatively high reactivity, Ag/CeOx catalysts are widely applied in catalytic oxidation of formaldehyde. However, lacking of accurate in situ characterization hinders the understanding of interfacial properties of CeO2/Ag catalysts and the role of the interface in the catalytic oxidation of formaldehyde reaction. In this project, we firstly apply in situ Localized Surface Plasmon Resonance-Mass spectroscopy (LSPR-MS) in the study of CO oxidation, which acts as a probe reaction, to discover the interaction between CeO2 and Ag and its role in the reaction process. Combined with in situ DRIFT and DFT calculations, we further take advantage of in situ LSPR-MS to establish the relation between the CeO2/Ag interface and the reaction mechanism of formaldehyde oxidation. Our study will provide fundamental understanding of catalytic oxidation of formaldehyde and guide CeO2/Ag catalyst optimization to further improve its reactivity.