Two‐Dimensional Metal‐Organic Frameworks and Covalent Organic Frameworks

Comprehensive Summary Two‐dimensional (2D) metal/covalent organic framework (MOF/COF) materials have ultra‐thin thickness and large surface area. These advantages bestow them the characteristics of low resistance and high flux in the process of material transportation. Meanwhile, more active sites promote their application in the fields of catalysis and sensing. Recently, 2D MOF/COF materials usher in a new wave of research. It is necessary to summarize the latest developments in this field in a timely and systematic manner and clarify future trends. In this review, we firstly introduce the advantages of 2D MOF/COF materials in hetero‐porous structure and functional modification. Then, we discuss advanced strategies for preparing 2D MOF/COF materials, such as in‐situ growth, interface synthesis, exfoliation method, electrochemical method, surfactant‐assisted synthesis, and laminated assembly of MOF/COF nanosheets. Finally, we summarize the applications of 2D MOF/COF materials in membrane separation, sensors, and energy storage. In addition, we discuss some unresolved scientific and technological challenges related to the future prospects of this field.