National Synchrotron Radiation Laboratory, University of Science and Technology of China, 230026 Hefei, China.
Institute of Nuclear Physics and Chemistry (INPC), China Academy of Engineering Physics (CAEP), Mianyang, 621900 Sichuan, China.
Inorg Chem. 2023 Jul 17;62(28):10881-10886. doi: 10.1021/acs.inorgchem.3c01458. Epub 2023 Jul 6.
Metal phosphonate frameworks (MPFs) consisting of tetravalent metal ions and aryl-phosphonate ligands feature a large affinity for actinides and excellent stabilities in harsh aqueous environments. However, it remains elusive how the crystallinity of MPFs influences their performance in actinide separation. To this end, we prepared a new category of porous, ultrastable MPF with different crystallinities for uranyl and transuranium separation. The results demonstrated that crystalline MPF was generally a better adsorbent for uranyl than the amorphous counterpart and ranked as the top-performing one for uranyl and plutonium in strong acidic solutions. A plausible uranyl sequestration mechanism was unveiled by using powder X-ray diffraction in tandem with vibrational spectroscopy, thermogravimetry, and elemental analysis.
金属膦酸盐框架（MPFs）由四价金属离子和芳基膦酸配体组成，对锕系元素具有很大的亲和力，并且在恶劣的水相环境中具有优异的稳定性。然而，MPFs 的结晶度如何影响其在锕系元素分离中的性能仍然难以捉摸。为此，我们为铀和超铀元素的分离制备了一类具有不同结晶度的新型多孔超稳定 MPF。结果表明，结晶 MPF 通常比无定形的 MPF 对铀酰具有更好的吸附能力，并且在强酸性溶液中对铀酰和钚的吸附能力是最强的。通过粉末 X 射线衍射与振动光谱、热重分析和元素分析相结合，揭示了一种合理的铀酰螯合机制。
