LAUSR

Abstract Polyamidoxime (PAO)-based adsorbents have been extensively studied for uranium (U) extraction from seawater for decades. “Hot alkali activation” treatments are found to significantly improve the U adsorption capacity while inevitably decrease the strength of PAO-based adsorbents, especially nanofiber adsorbents. Herein, for the first time, we report that, with proper modification, PAO can be dissolved in acid solution with high solubility, and the pre-acid-activated PAO (PA-PAO) exhibits high uranium capture ability (>1800 mg·g-1!). For better to use and collection in large scale application, PA-PAO is mixed with chitosan (CS) and fabricated to PA-PAO/CS nanofibers (NFs) via acidic aqueous solution blow spinning and glutaraldehyde vapor crosslinking. The covalently crosslinked PA-PAO/CS NFs are ready-to-use without post activation treatment, and achieve highly efficient U capturing performance in U spiked seawater (913.13 mg·g-1) and natural seawater (4.91 mg·g-, in 10 days), as well as enhanced mechanical stability and antibiofouling (antibacterial) activity. This strategy shows great potential for extraction of U from seawater and contaminated water in a cost-effective, industrial-scale manner.