Converging Cooperative Functions into the Nanospace of Covalent Organic Frameworks for Efficient Uranium Extraction from Seawater  

作　　者：Mengjie Hao Zhongshan Chen Xiaolu Liu Xianhai Liu Juyao Zhang Hui Yang Geoffrey I.N.Waterhouse Xiangke Wang Shengqian Ma 

机构地区：[1]College of Environmental Science and Engineering,North China Electric Power University,Beijing 102206 [2]MacDiarmid Institute for Advanced Materials and Nanotechnology,School of Chemical Sciences,The University of Auckland,Auckland 1142 [3]Department of Chemistry,University of North Texas,Denton,TX 76201

出　　处：《CCS Chemistry》2022年第7期2294-2307,共14页中国化学会会刊（英文）

基　　金：funding support from the National Science Foundation of China(grant nos.U2167218 and 22006036);National Key Research and Development Program of China(grant nos.2017YFA0207002 and 2018YFC1900105);the Science Challenge Project(grant no.TZ2016004);the Beijing Outstanding Young Scientist Program;the Students Innovation Training Program(grant no.202106014);the Robert A.Welch Foundation(B-0027)(S.M.);support from the 14W station in Shanghai Synchrotron Radiation Facility(SSRF).

摘　　要：The extraction of uranium from seawater is challenging though it offers tremendous potential for the sustainable production of nuclear fuel for the energy sector.Herein,we report a new strategy for efficient extraction of uranium from seawater via converging the cooperative functions of adsorption-photocatalysis into the nanospace of covalent organic frameworks(COFs).Functionalization of the organic linkers in the multicomponent COFs allowed exploration of the relationship between material composition and adsorption-photocatalytic activity for uranium extraction.The presence of amidoxime groups in the COFs offered selective binding sites for uranyl,whilst triazine units and bipyridine-Pd groups acted cooperatively to photocatalytically reduce adsorbed U(Ⅵ)to a U(Ⅳ)solid product(UO2)for facile collection.One of our developed COFs,4-Pd-AO,displayed exceptional performance in sequestering and reducing uranyl from natural seawater,with a high extraction capacity of 4.62 mg U/g per day(average data)under visible light irradiation.Mechanistic studies revealed that 4-Pd-AO not only reduced adsorbed uranyl(Ⅵ)to U(Ⅳ)O_(2),but also generated ^(1)O_(2) and superoxide radicals under visible light excitation,thus affording excellent antibacterial and antialgal activities(i.e.,antibiofouling properties)for sustained efficient uranium extraction performance.This proof-ofconcept study establishes multicomponent COFs as promising candidates for efficient uranium extraction from seawater.

关 键 词：covalentor ganic frameworks seawater uraniumextraction adsorption-photocatalysis COOPERATIVITY 

分 类 号：TL212[核科学技术—核燃料循环与材料]