In situ anchored nano zero-valent copper on ellagic acid-derived covalent organic frameworks: a dual-function strategy for antifouling and uranium enrichment from seawater

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 521; p. 166623
• Main Authors: Liu, Fenglei, Lu, Jiayu, Hu, Baowei
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2025
• Subjects: Covalent organic frameworks; Ellagic acid; Extraction; Seawater; U(VI); Covalent organic frameworks; U(VI); Extraction; Ellagic acid; Seawater
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2025.166623

Uranium extraction from seawater is regarded as an efficient approach to address the fuel supply issue in the development of nuclear energy. Herein, the covalent organic framework (EPCu-COF) was synthesized with the copper perfluorophthalocyanine and ellagic acid as construction units, and subsequent alkaline treatment and reduction reactions successfully led to the development of the dual-functional COFs (R-EPCu-COF-TA) for uranium extraction. Compared with EPCu-COF, the -COOH and -OH groups in the dual-functional COFs enhanced their hydrophilicity and selectivity, and the anchored Cu(0) not only reduced U(VI) but also exhibited effective antibacterial capabilities. The batch experiments found that R-EPCu-COF-TA exhibited a remarkable extraction capacity of 588.3 mg/g in the uranium-spiked seawater. Meanwhile, when subject to a 30 days extraction from natural seawater, the material's adsorption capacity for U(VI) reached 2.92 mg/g. More importantly, research into antibacterial properties showed that the R-EPCu-COF-TA had anti-bioadhesion capabilities, which could effectively inhibit bacterial growth. Mechanistic analysis demonstrated that U(VI) was initially coordinated by -COOH and -OH groups, then Cu(0) further reduced it to low-valence uranium. Thus, this COF holds extensive application prospects in the domain of uranium extraction from seawater. [Display omitted] •The dual-functional COFs were successfully synthesized via a two-step method.•This COF not only reduced U(VI) but also exhibited antibacterial capabilities.•Abundant -COOH/-OH groups promoted the mass transfer and diffusion of U(VI).•Removal mechanism involved surface complexation and redox reaction.