A Bifunctional Self‐Cycled Fenton System for Simultaneous Atmospheric Water Harvesting and Purification

Conventional atmospheric water harvesting technology is limited by air pollution, which threatens to contaminate the harvested water and undermine its safety. To address this challenge, we report a bifunctional, self‐cycled Fenton system that integrates airborne droplet capture with in situ purification for the direct production of clean water. The system is fabricated by a FeO X /ZnO(OVs)/Zn mesh, in which oxygen‐vacancy‐rich ZnO coupled with a Zn substrate continuously generates H 2 O 2 via electron transfer from the metallic Zn. The in situ produced H 2 O 2 is subsequently decomposed by the FeO X catalyst to yield highly reactive hydroxyl radicals (·OH), enabling simultaneous contaminant disinfection during fog collection. This self‐cycled design realizes continuous droplet harvesting and purification without external energy input (e.g., light or electricity), offering a self‐sustained strategy for atmospheric clean water harvesting. The system achieves nearly 99% removal of organic pollutants and a bacterial inhibition rate exceeding 99.99%. Furthermore, by incorporating the FeO X /ZnO(OVs)/Zn plate into a recirculation setup, we demonstrate its scalability for treating larger volumes of contaminated water. This work provides a sustainable, external‐energy‐free strategy to enhance water security in water‐stressed regions by addressing both water scarcity and safety challenges simultaneously.