Advances in the preparation and application of nanoconfined metal catalysts composed of porous materials

Nanoconfinement catalysis is becoming a research hotspot in the field of catalytic reactions due to its potential to enhance catalytic performance. Porous nanoconfined catalysts are designed by dispersing nanoparticles of active metal into porous support through various synthesis methods. This kind of catalyst can utilize the confinement effect of the pores to precisely regulate the dispersion and particle size of the metal particles, and then improve their catalytic activity and stability. During the process of catalytic reaction, the confinement effect of the pores in porous materials can effectively optimize the electronic states of the metal active components. Furthermore, the shape-selectivity of the pore channels can significantly improve the selectivity of the reaction products. This paper provides a comprehensive review of recent synthesized strategies for pore-confined metal nano-catalysts and their catalytic applications, and then delves into the mechanism by which the pore-confinement effect enhances catalytic activity, product selectivity, and the stability of catalysts. Specifically, the discussion is focused on various synthesis methods for pore-confined catalysts, including in situ encapsulated, core-shell structured, two-dimensional layered, and single-atom anchored catalysts, as well as recent advances of these catalysts in different catalytic reactions. Finally, the future prospect is proposed in order to provide a guidance for the development and application of pore-confined catalysts in catalytic reaction.