Crab‐Inspired Ion Capture in an Organic Electrode for High‐Capacity Electrochemical Desalination With Minimal Carbon Footprint

ABSTRACT The worsening global freshwater scarcity demands a paradigm shift toward sustainable desalination technologies. However, current approaches remain trapped in a persistent sustainability trilemma, marked by high energy consumption, heavy chemical dependence, and substantial carbon emissions. Here, we present an electrochemical desalination strategy that overcomes these limitations. Our design features a molecularly engineered organic electrode, bis(naphthoquinopyrazino)croconate (BNPC), integrated into a capacitive deionization (CDI) cell to enable seawater desalination through a crab‐inspired ion capture mechanism. Mimicking the coordinated grasping motion of crab claws, BNPC molecule adopts a distinctive dual‐arm architecture embedded with redox‐active sites, which provides a favorable coordination geometry that enhances ion mobility and diffusion while promoting electron delocalization to boost electrochemical ion capture performance. Module‐scale validation confirms the practical viability of this CDI approach, yielding industrial‐grade freshwater with a 97.6% yield ratio that meets WHO standards, alongside an exceptional desalination capacity of 378.2 mg g −1 . Beyond high‐capacity desalination performance, the process operates with low energy consumption and a carbon footprint of only 0.216 t CO 2 eq per ton of salt removed, which is lower than that of state‐of‐the‐art desalination technologies. This molecular‐level electrode design offers a feasible pathway toward carbon‐lean and energy‐efficient desalination, bridging critical gaps in the water‐energy nexus.