Uranium-bearing wastewaters exert a great threat to the ecological environment due to its high radiotoxicity level. The designing and fabrication of novel adsorption materials can be promoted for radionuclide elimination from wastewater. In this work, results from density functional theory and Born–Oppenheimer molecular dynamics simulations are reported for the uranyl adsorption behavior on the MoS₂/Mo₂CT_x heterostructure in the gas phase and in an aqueous environment. Uranyl ions prefer to be adsorbed at deprotonated O sites on the Mo₂COH surface and S sites on the MoS₂ side of the heterojunctions, resulting in the formation of bidentate configurations. In addition to coordination interaction, H-bond and van der Waals interactions can also play an important role in binding configurations. More importantly, the oxidation state U(VI) can be reduced to U(V) and then to U(IV) caused by the strong reducibility of the Mo₂COH surface at room temperature, whereas the uranyl complex can move freely on the MoS₂ surface. However, the coordination number of U with respect to H₂O in the first hydration shell on the Mo₂COH surface remains unchanged and is found to be 3, which is similar to that on the MoS₂ surface. This work provides novel nanosorbents for the removal of uranyl from wastewater. The present viewpoint provides valuable mechanistic interpretations for uranyl adsorption and will give a supplement to the experimental research.

中文翻译：

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使用 DFT 和 BOMD 方法模拟铀酰在 MoS2/Mo2CTx 异质结构上的吸附

含铀废水由于其高放射毒性水平，对生态环境造成了巨大威胁。新型吸附材料的设计和制造可以促进废水中放射性核素的去除。在这项工作中，报告了密度泛函理论和 Born-Oppenheimer 分子动力学模拟的结果，以了解气相和水环境中铀酰在 MoS ₂ /Mo ₂ CT _{x异质结构上的吸附行为。}铀酰离子更倾向于吸附在 Mo ₂ COH 表面的去质子化 O 位点和 MoS _{2表面的 S 位点}异质结的一侧，导致双齿配置的形成。除了配位相互作用，氢键和范德华力相互作用也可以在结合构型中发挥重要作用。_{更重要的是，由于 Mo 2} COH 表面在室温下的强还原性，氧化态 U(VI) 可以还原为 U(V)，然后还原为 U(IV)，而铀酰络合物可以在 MoS 上自由移动₂表面。_{然而，Mo 2} COH表面第一水合壳层中U相对于H ₂ O的配位数保持不变，为3，这与MoS _{2上的相近}表面。这项工作为去除废水中的铀酰提供了新型纳米吸附剂。目前的观点为铀酰吸附提供了有价值的机理解释，并将为实验研究提供补充。