More Yogeshwar D, Mollick Samraj, Saurabh Satyam, Fajal Sahel, Tricarico Michele, Dutta Subhajit, Shirolkar Mandar M, Mandal Writakshi, Tan Jin-Chong, Ghosh Sujit K
Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India.
Multifunctional Materials & Composites (MMC) Laboratory, Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, UK.
Small. 2024 Jan;20(3):e2302014. doi: 10.1002/smll.202302014. Epub 2023 Sep 12.
On-demand uranium extraction from seawater (UES) can mitigate growing sustainable energy needs, while high salinity and low concentration hinder its recovery. A novel anionic metal-organic framework (iMOF-1A) is demonstrated adorned with rare Lewis basic pyrazinic sites as uranyl-specific nanotrap serving as robust ion exchange material for selective uranium extraction, rendering its intrinsic ionic characteristics to minimize leaching. Ionic adsorbents sequestrate 99.8% of the uranium in 120 mins (from 20,000 ppb to 24 ppb) and adsorb large amounts of 1336.8 mg g and 625.6 mg g from uranium-spiked deionized water and artificial seawater, respectively, with high distribution coefficient, K ≥ 0.97 × 10 mL g . The material offers a very high enrichment index of ≈5754 and it achieves the UES standard of 6.0 mg g in 16 days, and harvests 9.42 mg g in 30 days from natural seawater. Isothermal titration calorimetry (ITC) studies quantify thermodynamic parameters, previously uncharted in uranium sorption experiments. Infrared nearfield nanospectroscopy (nano-FTIR) and tip-force microscopy (TFM) enable chemical and mechanical elucidation of host-guest interaction at atomic level in sub-micron crystals revealing extant capture events throughout the crystal rather than surface solely. Comprehensive experimentally guided computational studies reveal ultrahigh-selectivity for uranium from seawater, marking mechanistic insight.
从海水中按需提取铀（UES）可以缓解不断增长的可持续能源需求，而高盐度和低浓度阻碍了铀的回收。一种新型阴离子金属有机框架（iMOF-1A）被证明装饰有罕见的路易斯碱性吡嗪位点，作为铀酰特异性纳米阱，用作选择性提取铀的强大离子交换材料，利用其固有离子特性将浸出降至最低。离子吸附剂在120分钟内螯合99.8%的铀（从20,000 ppb降至24 ppb），并分别从加铀去离子水和人工海水中吸附大量的1336.8 mg g和625.6 mg g，分配系数K≥0.97×10 mL g。该材料具有约5754的非常高的富集指数，在16天内达到6.0 mg g的UES标准，在30天内从天然海水中收获9.42 mg g。等温滴定量热法（ITC）研究量化了热力学参数，这在以前的铀吸附实验中尚未有过记录。红外近场纳米光谱（nano-FTIR）和尖端力显微镜（TFM）能够在亚微米晶体中以原子水平对主客体相互作用进行化学和机械阐释，揭示整个晶体而非仅表面上存在的捕获事件。全面的实验指导计算研究揭示了对海水中铀的超高选择性，标志着对其机理的深入理解。
