Strategies for designing highly efficient adsorbents to capture uranium from seawater

Mining uranium from seawater using highly efficient adsorbents has been redeemed as one of the most urgent demands for sustainable nuclear power. However, it remains a formidable task to achieve sufficient extraction capacities for practical applications given the trace concentration of uranium (∼3.3 ppb), the competition from massive coexisting ions, and the extreme complexity of marine environment. This review briefly introduces the coordination chemistry behind uranium extraction from seawater (UES). Subsequently, we summarize and discuss existing strategies for designing highly efficient UES adsorbents toward one or more desired directions (such as high affinity, high selectivity, fast kinetics, and excellent antifouling property) to boost the uptake capacity in natural seawater. They mainly include adsorption through optimization of ligands, bifunctional synergy, bioinspired and biomimetic, molecular imprinting, electrically driven and photo-driven strategies, and antimicrobial and antifouling strategies. Finally, four critical perspectives regarding the design strategies of UES adsorbents are highlighted. The goal of this review is to assist researchers in this field in designing promising adsorbents for practical UES.