High-adsorption-capacity and recyclable double-network hydrogel nanofibers for dynamic uranium sorption

Extracting uranium (U) from seawater is an important future energy development direction. Due to the shortcomings of traditional uranium adsorption systems, double-network hydrogel nanofibers were fabricated via electrospinning and steam crosslinking. These hydrogel nanofibers combined the unique beaded network structure of electrospun nanofibers and the flexibility of a double-network hydrogel. The stretched PAO molecular chains in the hydrogel nanofibers provided a larger specific surface area and more binding sites that could combine with U. According to the results, the hydrogel nanofibers exhibited high water permeability, high hydrophilicity, high adsorption efficiency, rapid filtration, and a high recycling rate during uranium extraction. Moreover, an average adsorption capacity of 134 mg-U/g was obtained after 30 h of immersion in dilute U-containing seawater via a flow-through column system. These new hydrogel nanofibers show great potential as a next-generation adsorbent for uranium extraction from seawater.