Pt-MOx催化剂界面结构调控及其强化甘油酸合成机制研究

甘油酸是一种广泛应用于食品、医药等行业中的高端专用化学品。然而，生物基甘油在无碱条件下氧化生成高附加值甘油酸的过程中，目前传统的Pt基催化剂表面电子密度低、吸附位点单一，导致其对O-H、C-H键活化能力弱、C=O键吸/脱附强度不可控，产生了甘油反应活性差、甘油酸产物收率低的瓶颈问题。本工作以调控Pt-MOx（M=Zn或Mn）催化剂界面结构为切入点，通过电子效应丰富Pt表面的电子，促进甘油分子中O-H、C-H键的活化，提高催化活性；利用协同吸附效应控制甘油酸产物中C=O键的吸附强度，抑制C-C键断裂等副反应的发生，提高甘油酸收率。与此同时，结合实验关键制备参数优化和理论计算辅助界面结构设计，发展高效Pt-MOx界面结构的定向调控技术；建立界面结构与O-H、C-H、C=O键活化/脱附能力的对应关系，阐明界面活性位上甘油酸的合成机理，为高效、绿色的多元醇氧化反应的产业化提供重要的理论和技术支持。

Glyceric acid is a kind of high-end special chemical, which has been widely used in food, medicine and other industries. However, in the process of bio-glycerol oxidation to produce high value-added glyceric acid product under alkali free conditions, the traditional Pt-based catalyst exhibits low surface electron density and single adsorption site, resulting in the weak activation ability of O-H and C-H bonds and uncontrollable adsorption/desorption strength of C=O bond. Therefore, the problems of poor catalytic activity and low yield of glyceric acid product were caused. In this work, engineering Pt-MOx (M=Zn or Mn) interface was served as the breakthrough point to solve the above problems. The Pt-MOx interface could enrich the surface electrons of Pt via electronic coupling effect, promoting the activation of O-H and C-H bonds in glycerol molecule. Therefore, the catalytic activity was improved. Moreover, the adsorption strength of C=O bond in the glyceric acid could be controlled by the synergistic adsorption effect of the Pt-MOx interface, inhibiting the side reactions such as C-C bond cleavage. Consequently, the yield of glyceric acid was increased. Meanwhile, combined with the optimization of key experimental preparation parameters and theoretical calculation, a directional control technology for the efficient Pt-MOx interface structure was developed. In addition, the corresponding relationships between catalyst structure and the activation ability or desorption behavior of O-H, C-H and C=O bonds were established, and the synthesis mechanism of glyceric acid on the active site of the Pt-MOx interface was clarified. This work could provide important theoretical and technical support for the industrialization of efficient and green polyol oxidation reaction.