Photothermal‐Enhanced Uranium Extraction from Seawater: A Biomass Solar Thermal Collector with 3D Ion‐Transport Networks

Access to uranium resources is critical to the sustainable development of nuclear energy. The ocean contains abundant uranium resources, but the marine biological pollution and the low concentration of uranium make it a giant challenge to extract uranium from seawater. On the foundation of selective uranium adsorption using high uranium‐affinity groups, realizing the external‐field improved uranium capture without extra energy consumption is highly attractive. A solar thermal collector with 3D ion‐transport networks based on environmentally friendly biomass adsorption material is reported, which contains antibacterial adsorption ligands and photothermal graphene oxide. The antibacterial ability through an easy one‐step reaction and the fast mass transfer caused by photothermal conversion collaboratively improve the original adsorption capacity of the hydrogel by 46.7%, reaching 9.18 mg g−1 after contact with natural seawater for 14 days. This study provides a universal strategy for the design of physical‐fields‐enhanced hydrogel adsorbents. A phosphate‐group‐based solar biomass thermal collector with antibacterial ability is designed to extract uranium from seawater effectively. The photothermal conversion of GO and the antibacterial ability of quaternary ammonium functional groups promote the coordination of uranium with binding sites and accelerate ion transport while uranium capture, which can significantly increase the adsorption performance of hydrogel‐based sorbents.