Selective and antibacterial zinc phosphonate framework system for superior marine uranium harvesting

Efficient utilization of uranium in seawater provides a viable and sustainable solution to supply the growing demand for nuclear energy. Adsorbents used for uranium extraction from seawater are usually disturbed by co-existing ions and contaminated by organisms. In this study, a zinc phosphonate framework system (ZMP2-6) with zoledronic acid as a ligand was fabricated via a facile one-step mixing method at room temperature, which possesses great adsorption performance, high selectivity and outstanding antibacterial ability. The high porosity and rich binding sites endowed ZMP2-6 with an extremely high adsorption capacity of 1695.5 mg/g at 25°C. Remarkably, ZMP2-6 selectively extracted 18.0 mg/g uranium from natural seawater in only 1 month with a higher distribution coefficient against other coexisting metal ions. In addition, ZMP2-6 exhibited excellent bacteriostatic ability against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), which was greatly desired in real uranium extraction from seawater. Noteworthily, ZMP2-6 can be easily assembled into adsorption modules and grow on different carriers, which significantly improves uranium separation efficiency and practical applicability. This work rationally engineered a zinc phosphonate framework system and provided a strategy for highly efficient uranium capture from the ocean.