Macrocyclic membranes: from liquid to solid state

Membrane science and technology have undergone rapid development, assuming increasingly critical roles in high-tech industries. The emergence of macrocyclic-based membranes has introduced transformative innovations to the scientific community. Distinct from conventional membranes, these systems exhibit intrinsic nanoporosity with uniform pore distribution, coupled with remarkable host-guest/supramolecular properties/chemical versatility/tunable functionality or their combined properties. The inherent structural features of the macrocyclic membranes offer new avenues for advancing the membrane fields. Such characteristics position macrocyclic membranes as next-generation high-performance platforms with demonstrable potential to advance membrane research and industrial applications. This tutorial review presents a cohesive perspective on cutting-edge advancements in macrocyclic membranes, encompassing progress in macrocycle design, membrane architectures, interfacial assembly behavior, and transport mechanisms across liquid and solid membrane systems. Particular attention is given to applications in energy storage, desalination, and related fields, offering promising solutions to global challenges including energy sustainability and water scarcity. Finally, the current challenges, potential applications, and prospects of macrocyclic membranes are outlined and discussed.