High‐Performance Artificial Lithium Channel Enabled by a Brominated Organic Imine Cage

ABSTRACT Despite extensive advancements in the design of artificial transporters for K + , Cl − and water, the development of Li + ‐selective systems has remained comparatively neglected, largely due to its smaller ionic radius and higher hydration energy that pose significant design challenges. To date, only three classes of artificial Li + transporters have been reported. In this work, we introduce a novel fourth class of artificial Li + channels, constructed from unique self‐assembling organic imine cages that form membrane‐spanning porous architectures. By incorporating bromine substituents, the resulting channel exhibits not only the highest Li + transport activity (EC 50 of 0.017 mol‰, relative to lipids) but also unprecedented selectivity, with Li + /Na + and Li + /K + selectivity factors of 44 and 52 respectively, marking a new benchmark in transmembrane Li + transport performance.