Covalent Organic Framework Hydrogel for Synergistic Seawater Desalination and Uranium Extraction

Fresh water and energy are among the major challenges to the development of human civilization. Herein, we report the concept of covalent organic framework hydrogels (named CPP) as a synergistic platform for seawater desalination and uranium extraction. In natural seawater, CPP shows an exceptional evaporation rate (0.744 kg m-2 h-1) and uranium extraction capacity (4.15 mg g-1), which benefits from: a hydrophilic 3D hydrogel network and capillary microporous channel of CPP providing adequate water transport, improving the mass transfer of uranyl, and increasing the binding sites of uranyl. In addition, CPP exploits interfacial solar heating to limit heat, increases solar energy utilization, and further accelerates the coordination between uranium and binding sites. Excellent photocatalytic effects endow CPP with high anti-biofouling activity, achieving long-term solar desalination and highly efficient uranium extraction. The connection between freshwater and nuclear energy is realized in a new material providing an opportunity to meet the growing needs of mankind.