Bioinspired Large-Area Polymeric Cucurbituril Monolayers with Ultrahigh-Density Nanopores Enabling Reversible Charge-Gating of Ion Transport via Host-Guest Recognition.

Achieving precise control over ion and molecular transport under subnanometer confinement, especially beyond passive sieving, remains challenging in nanofluidics and membrane science. Here, we present a bioinspired strategy that enables the formation of subnanometer channels together with the integration of tunable molecular recognition within 2D amorphous polymer membranes. Large-area membranes with a size up to 900 cm2 were fabricated by interfacial cross-linking of supramolecular assemblies. Molecular-level control over the amphiphilicity of cucurbituril host-guest complexes (HGCs) yields 1.6 nm thick amorphous monolayers with subnanometer pores at a high density of (1.5 ± 0.5) × 1013 cm-2, comparable to that of covalent organic frameworks (COFs). The nanopores formed between cucurbituril hosts serve as dense transport pathways, while the intrinsic cavities act as dynamic host-guest recognition sites. This architecture enables reversible charge-gating of ion transport via host-guest recognition and delivers outstanding performance in osmotic power generation. This work provides a design strategy for constructing adaptive transport systems, introducing dynamic functionality into otherwise static porous architectures, with potential applications for responsive separation and advanced energy harvesting.