金属有机框架衍生的单原子纳米酶的理性构建与活性研究

近年来，由于具有与天然酶相似的M-Nx活性位点，M-N-C单原子催化剂（SACs）作为一种新型纳米酶逐渐引起了人们的关注。与其电催化性质相比，人们对M-N-C SACs类酶性质的认识还很初步，相关研究集中在Fe-N-C体系，且面临着构效关系不够明确、活性位点利用率低、稳定性有待提高等诸多关键科学问题。鉴于此，本项目以MOF热解得到的M-N-C SACs作为研究对象，在完善M-Nx活性中心精准构筑的基础上，系统研究不同金属（Fe, Cu, Ni, Mn, Cu, Zn）活性中心的类酶催化机制，探明催化剂在实际应用过程中活性下降的原因；在此基础上，通过构建双金属M-Nx活性中心、优化表观形貌及微孔结构，提高材料的模拟酶活性和稳定性，通过构筑Au/M-N-C SACs多酶串联体系探索其在生物医学方面的应用。我们相信，这项工作可为高效、稳定的类酶活性材料的理性构建奠定理论和实践基础。

In recent years, M-N-C single atom catalysts (SACs), which possess similar M-Nx active sites with natural enzymes, have attracted increasing attentions due to its potential as a bridge to understand the structure-activity relationship between nanozymes and natural enzymes. However, recent research on the enzymes-like activity of M-N-C SACs is mainly focused on the Fe-N-C system, and the understanding of its structure-activity relationship is very preliminary. Especially, there are still many key problems to be addressed in the practical application of M-N-C SACs at present. For example, the actual utilization rate of M-Nx active sites is not as high as expected, and the catalytic activity is always decreased due to the structure damage of M-Nx active sites caused by the Fenton reaction. In this project, we will focus our search on the rational construction of metal organic frameworks derived M-N-C SACs for enhancing enzyme-like activity. We hope to explore M-N-C SAzymes with high activity and stability through a reasonable design and engineering of the apparent morphology and M-Nx sites of catalysts. First, we will systematically investigate the enzymes-like activities of M-N-C SACs with different M-Nx (M=Fe, Cu, Ni, Mn, Cu, Zn) active centers, establish their structure-activity relationship, and clarify their deactivation mechanism in the practical application. On this basis, we intend to further improve the enzymes-like activity and stability of M-N-C SACs by means of constructing bimetal M-Nx active sites as well as optimizing the morphology and micropores of catalysts. Furthermore, we will construct a novel multi-enzyme tandem system based on Au/M-N-C SAC hybrids and explore its potential applications in glucose detection and antibacterial fields. We believe this work will open up a new horizon for the exploration of M-N-C SACs in the field of enzymatic catalysis and biological applications.