Mechanically Interlocked Macrocycles on Covalent Networks for Energy and Environmental Applications.

Macrocycles' unique properties of interacting with guest molecules have been an intriguing scientific endeavor for many decades. They are potentially practically useful for engineering applications, especially in energy and environmental applications. These applications are usually demanding, involving a high temperature, pH, voltage, etc., thus, finding suitable substrates that can endure working environments and sustain macrocycles' properties is highly desirable. In that sense, covalent networks are ideal as they are chemically/electrochemically/thermally stable and can be porous by design. Emerging porous materials, especially covalent organic frameworks (COFs), could be suitable as their porous spaces allow macrocycles to interact with guest species. In the past seven years, we have seen the rise of mechanically interlocked macrocycles on covalent networks (MIMc-CNs) that translate macrocycles' properties into macroscale materials. In this conceptual review, we first describe the idea of integrating MIMcs into COFs or conventional amorphous polymers. Next, we review the reported representative MIMc-CNs used in energy and environmental applications. We also provide a brief outlook for the future directions for the MIMc-CNs research.