Highly Sensitive and Selective Uranium Detection in Natural Water Systems Using a Luminescent Mesoporous Metal-Organic Framework Equipped with Abundant Lewis Basic Sites: A Combined Batch, X-ray Absorption Spectroscopy, and First Principles Simulation Investigation.
Wei LiuXing DaiZhuanling BaiYanlong WangZaixing YangLinjuan ZhangLin XuLanhua ChenYuxiang LiDaxiang GuiJuan DiwuJianqiang WangRuhong ZhouZhifang ChaiShu-Ao WangPublished in: Environmental science & technology (2017)
Uranium is not only a strategic resource for the nuclear industry but also a global contaminant with high toxicity. Although several strategies have been established for detecting uranyl ions in water, searching for new uranium sensor material with great sensitivity, selectivity, and stability remains a challenge. We introduce here a hydrolytically stable mesoporous terbium(III)-based MOF material compound 1, whose channels are as large as 27 Å × 23 Å and are equipped with abundant exposed Lewis basic sites, the luminescence intensity of which can be efficiently and selectively quenched by uranyl ions. The detection limit in deionized water reaches 0.9 μg/L, far below the maximum contamination standard of 30 μg/L in drinking water defined by the United States Environmental Protection Agency, making compound 1 currently the only MOF material that can achieve this goal. More importantly, this material exhibits great capability in detecting uranyl ions in natural water systems such as lake water and seawater with pH being adjusted to 4, where huge excesses of competing ions are present. The uranyl detection limits in Dushu Lake water and in seawater were calculated to be 14.0 and 3.5 μg/L, respectively. This great detection capability originates from the selective binding of uranyl ions onto the Lewis basic sites of the MOF material, as demonstrated by synchrotron radiation extended X-ray adsorption fine structure, X-ray adsorption near edge structure, and first principles calculations, further leading to an effective energy transfer between the uranyl ions and the MOF skeleton.
Keyphrases
- metal organic framework
- quantum dots
- drinking water
- aqueous solution
- energy transfer
- high resolution
- loop mediated isothermal amplification
- label free
- real time pcr
- sensitive detection
- water soluble
- risk assessment
- air pollution
- magnetic resonance imaging
- oxidative stress
- computed tomography
- molecularly imprinted
- dual energy
- single molecule
- health risk
- health risk assessment
- human health
- density functional theory
- transcription factor
- living cells
- molecular dynamics simulations
- radiation therapy