Chen Zhe, Chen Wanying, Jia Dashuang, Liu Yang, Zhang Anrui, Wen Tao, Liu Jian, Ai Yuejie, Song Weiguo, Wang Xiangke
College of Environmental Science and Engineering North China Electric Power University Beijing 102206 P. R. China.
Laboratory of Molecular Nanostructures and Nanotechnology Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China.
Adv Sci (Weinh). 2018 Aug 27;5(10):1800235. doi: 10.1002/advs.201800235. eCollection 2018 Oct.
The development of functional materials for the highly efficient capture of radionuclides, such as uranium from nuclear waste solutions, is an important and challenging topic. Here, few-layered N, P, and S codoped graphene-like carbon nanosheets (NPS-GLCs) that are fabricated in the 2D confined spacing of silicate RUB-15 and applied as sorbents to remove U(VI)ions from aqueous solutions are presented. The NPS-GLCs exhibit a large capacity, wide pH suitability, an ultrafast removal rate, stability at high ionic strengths, and excellent selectivity for U(VI) as compared to multiple competing metal ions. The 2D ultrathin structure of NPS-GLCs with large spacing of 1 nm not only assures the rapid mass diffusion, but also exposes a sufficient active site for the adsorption. Strong covalent bonds such as P-O-U and S-O-U are generated between the heteroatom (N, P, S) with UO according to X-ray photoelectron spectroscopy analysis and density functional theory theoretical calculations. This work highlights the interaction mechanism of low oxidation state heteroatoms with UO , thereby shedding light on the material design of uranium immobilization in the pollution cleanup of radionuclides.
开发用于高效捕获放射性核素（如从核废料溶液中捕获铀）的功能材料是一个重要且具有挑战性的课题。在此，本文介绍了在硅酸盐RUB - 15的二维受限空间中制备的少层氮、磷和硫共掺杂类石墨烯碳纳米片（NPS - GLCs），并将其用作吸附剂以从水溶液中去除U(VI)离子。与多种竞争性金属离子相比，NPS - GLCs具有大容量、宽pH适用性、超快去除速率、在高离子强度下的稳定性以及对U(VI)的优异选择性。具有1 nm大间距的NPS - GLCs二维超薄结构不仅确保了快速的质量扩散，还暴露了足够的吸附活性位点。根据X射线光电子能谱分析和密度泛函理论计算，杂原子（N、P、S）与UO之间形成了诸如P - O - U和S - O - U等强共价键。这项工作突出了低氧化态杂原子与UO的相互作用机制，从而为放射性核素污染清理中铀固定化的材料设计提供了思路。
