Electrically Modulating the Binding Affinity of Coordination Atoms on Conductive Polymers for Rapid Uranium Capture

ABSTRACT Electrochemical methods offer great potential for the capture of soluble uranium, yet metal ions accumulate on the electrode surface under electrostatic attraction, reducing the selectivity and rate of uranium ion extraction. Herein, three types of conductive polymers—those with high‐density, low‐density, and no electrically mediated binding units, respectively—were introduced into the nano‐channels of ordered mesoporous carbon (CMK‐3). Under a negative bias, the binding affinities of nitrogen and sulfur coordination units on poly(aminothiazole) (PAT) chains were electrically balanced, which transported the uranyl ions along the conductive PAT chains. Upon removal of the bias, the PAT chains in the confined space immobilized uranyl ions through the formation of a quadruple coordination structure, effectively excluding interfering ions. The PAT‐based solid reveals an ultra‐fast ion adsorption speed of 259.9 mg g −1 in the first 5 min of contact from 10 ppm uranium‐spiked water, while achieving high selectivity (U/V selectivity coefficient over 38.2). In particular, it demonstrated a high extraction capacity from natural seawater (∼3.3 ppb), surpassing that of classical amidoxime‐based adsorbents without electrically mediated binding units by a factor of 1115%.