Selective extraction of uranium from seawater with biofouling-resistant polymeric peptide

Nuclear power could continue to be a reliable and carbon-free energy source at least from a near-term perspective. In addition to the safety issues, another risk that may threaten the sustainability of this technology is the uranium supply disruption. As opposed to the land-based deposits, the ocean contains 1,000 times more uranium reserves and provides a more abundant resource for uranium. However, due to the very low concentration and presence of many other metal ions as well as the accumulation of microorganisms, the development of uranium extraction technology faces enormous challenges. Here we report a bifunctional polymeric peptide hydrogel that shows not only strong affinity to and selectivity for uranium in seawater but also remarkable resistance against biofouling. Detailed characterizations reveal that the amino acid in this peptide material serves as the binding ligand, and uranyl is exclusively bound to the oxygen atoms. Benefiting from its broad-spectrum antimicrobial activity, the present polymeric adsorbent can inhibit the growth of approximately 99% of marine microorganisms. Measurements in natural seawater show that this peptide material delivers an impressive extraction capacity of 7.12 mg g−1 and can be reused. This work opens a new direction for the design of low-cost and sustainable materials for obtaining nuclear fuel.