基于机械化学策略宏量制备系列单原子催化剂的研究

单原子催化剂因其极高的金属利用率、独特的电子/几何结构和优异的催化性能，受到学术界的高度重视。但是，目前大多数合成方法，仍存在制备工艺复杂、生产成本高、伴随环境污染等问题，特别是普遍存在放大效应，即无法保证在宏量制备的前提下，维持金属物种原子级分散的精细结构，进而维持优异的催化性能。.申请人针对这一学术前沿，基于前期工作基础，引入机械化学这一新颖策略，初步实现氧化锌负载钯单原子催化剂等体系从毫克/克级到千克级制备量级的飞跃。但是其内在的物理化学变化机制仍有待研究。本项目拟在上述发现的基础上，筛选出影响金属物种原子级分散的关键因素，阐明机械力在金属分散过程中的作用机制，并给出消除放大效应的基本方法，进而实现一系列单原子催化剂的宏量制备。并以丙烷脱氢和二氧化碳还原为模型反应详细考察其催化性能，从而为该材料的进一步发展提供理论指导和技术依据。

Single atom catalysts (SACs) are becoming highly attractive to academia because of the maximum utilization of metal species, unique electronic/geometric structures, and superior catalytic properties. However, although many synthesis methods of SACs have been reported, there are still several drawbacks that should be overcome, including the tedious procedures, the high costs, the serious pollution, and especially the magnification effects. The magnification effects prevail in current available synthesis procedure, which means it is very challenging to keep the fine structure of isolated metal sites and thus the excellent catalytic performance during the scale-up procedure..Our preliminary work has established a scalable approach for the production of supported Pd SACs via a mechanical milling (mechanochemistry) in kilogram scale. However, the dispersion mechanism of metal species under the conditions of mechanochemistry is still ambiguous, and thus the application scope of this approach is also unclear. This project aims to enrich the applications of this macroscopic production approach to various SACs for propane dehydrogenation and CO2 reduction reactions. Various factors that influence the dispersion state of metal species will be investigated systematically and the inherent mechanism of mechanochemistry during the milling process of the metal precursors will be elucidated. The basic method to eliminate the magnification effects will also be established, and then the mass production of a series of SACs will be achieved. The project is expected to enrich the synthesis methodology of SACs and develop the theoretical and technological basis for their practical applications.