Sun Ningru, Sun Lei, Peng Zhenbo, Shen Xiaolan, Liu Zhen, Qiu Nianxiang, Xu Zhongjie, Su Minru, Du Shiyu
School of Chemical Engineering, Ningbo Polytechnic, Ningbo 315800, China.
Ningbo Key Laboratory of High Performance Petroleum Resin Preparation Engineering and Technology, Ningbo Polytechnic, Ningbo 315800, China.
ACS Omega. 2025 Aug 13;10(33):37505-37513. doi: 10.1021/acsomega.5c03463. eCollection 2025 Aug 26.
One of the most critical steps in the treatment of spent nuclear fuel is the removal of americium (Am) and curium (Cm) ions from radioactive wastewater. The use of new materials with high surface areas, such as graphene, has been considered a promising solution to this issue. Therefore, understanding the mechanism by which Am and Cm ions are adsorbed onto the graphene surface in aqueous solutions is of paramount importance. In this study, we have investigated 12 complexes formed between americium (Am) and curium (Cm) ions and graphene oxide (GO) using density functional theory (DFT), combined with quasi-relativistic small-core pseudopotentials. The structures, bonding characteristics, and energies of Am-(III) and Cm-(III) complexes with graphene oxide modified by hydroxyl (-OH), carboxyl (-COOH), amide (-CONH), and dimethylamide (-CONMe) groups have been explored. It can be observed that the distances between the actinide atom and the oxygen atom in the functional groups on graphene (An-OG) vary significantly across different complexes. The coordination bond in the [Cm-(HO)]/GO complex exhibits the shortest bond lengths, suggesting the presence of more stable hydrogen bonds. This indicates that the [Cm-(HO)] ion can be more easily adsorbed onto GO. Furthermore, thermodynamic calculations show that the binding strength of Am ions toward GO modified with hydroxyl and dimethylformamide groups is significantly stronger than that of the complexes with carboxyl and amido groups. These results will inform the development of high-efficiency nanoscale scavengers for radioactive contaminant removal.
乏核燃料处理过程中最关键的步骤之一是从放射性废水中去除镅（Am）和锔（Cm）离子。使用具有高表面积的新材料，如石墨烯，被认为是解决这一问题的一个有前景的方案。因此，了解镅和锔离子在水溶液中吸附到石墨烯表面的机制至关重要。在本研究中，我们使用密度泛函理论（DFT）并结合准相对论小核赝势，研究了镅（Am）和锔（Cm）离子与氧化石墨烯（GO）形成的12种配合物。探索了用羟基（-OH）、羧基（-COOH）、酰胺基（-CONH）和二甲基酰胺基（-CONMe）修饰的氧化石墨烯与Am-(III)和Cm-(III)配合物的结构、键合特性和能量。可以观察到，不同配合物中，石墨烯官能团上的锕系元素原子与氧原子之间的距离（An-OG）差异显著。[Cm-(HO)]/GO配合物中的配位键键长最短，表明存在更稳定的氢键。这表明[Cm-(HO)]离子更容易吸附到GO上。此外，热力学计算表明，镅离子与羟基和二甲基甲酰胺基修饰的GO的结合强度明显强于与羧基和酰胺基形成的配合物。这些结果将为开发用于去除放射性污染物的高效纳米级清除剂提供参考。
