Constructing 2D Polyphenols‐Based Crosslinked Networks for Ultrafast and Selective Uranium Extraction from Seawater

Abstract The role of tannins (TA), a well‐known abundant and ecologically friendly chelating ligand, in metal capture has long been studied. Different kinds of TA‐containing adsorbents are synthesized for uranium capture, while most adsorbents suffer from unfavorable adsorption kinetics. Herein, the design and preparation of a TA‐containing 2D crosslinked network adsorbent (TANP) is reported. The ≈1.8‐nanometer‐thick TANP films curl up into micrometer‐scale pores, which contribute to fast mass transfer and full exposure of active sites. The coordination environment of uranyl (UO 2 2+ ) ions is explored by integrated analysis of U L3‐edge XANES and EXAFS. Density functional theory calculations indicate the energetically favorable UO 2 2+ binding. Consequently, TANP with excellent adsorption kinetics presents a high uranium capture capacity (14.62 mg‐U g‐Ads −1 ) and a high adsorption rate (0.97 mg g −1 day −1 ) together with excellent selectivity and biofouling resistance. Life cycle assessment and cost analysis demonstrate that TANP has tremendous potential for application in industrial‐scale uranium extraction from seawater.