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As a critical radioactive anionic contaminant, traditional adsorbents primarily remove iodate (IO3−) through ion exchange or hard acid‐hard base interactions, but suffer from limited affinity and capacity. Herein, employing the synergistic effect of ion exchange and redox, we successfully synthesized a redox‐active cationic polymer network (SCU‐CPN‐6, [C9H10O2N5 ⋅ Cl]n) by merging guanidino groups with ion‐exchange capability and phenolic groups with redox ability via a Schiff base reaction. SCU‐CPN‐6 exhibits a groundbreaking adsorption capacity of 896 mg/g for IO3−. The inferior adsorption capacities of polymeric networks containing only redox (~0 mg/g) or ion exchange (232 mg/g) fragments underscore the synergistic "1+1>2" effect of the two mechanisms. Besides, SCU‐CPN‐6 shows excellent uptake selectivity for IO3− in the presence of high concentrations of SO42−, Cl−, and NO3−. Meanwhile, a high distribution coefficient indicates its exemplary deep‐removal performance for low IO3− concentration. The synergic strategy not only presents a breakthrough solution for the efficient removal of IO3− but also establishes a promising avenue for the design of advanced adsorbents for diverse applications. [ABSTRACT FROM AUTHOR]

Efficient removal of iodide (I−) and iodate (IO3−) from aqueous solution is highly desirable for waste disposal and remediation of radioiodine contamination. We report here a bifunctional anion exchange resin Purolite A530E for the effective I−/IO3− adsorption, which shows a priority anion-exchange affinity for I− (99%) over IO3− (9.7%). The maximum adsorption capacity for I− is 275.16 mg·g−1 fitted by the Langmuir isotherm model, much higher than most adsorbents. Furthermore, Purolite A530E exhibits great selectivity for I− over competing anions, which endows the resin with promising I− remediation that over 99% I− can be removed from simulated Hanford groundwater (HGW). [ABSTRACT FROM AUTHOR]

A novel 3D potassium-containing zirconium fluorophosphonate K2Zr[CH2(PO3)2]F2 (SZ-8) was successfully synthesized as single crystals via a solvothermal method using a mixture of nitric acid and potassium nitrate as mineralizers. SZ-8 can adsorb 110.6 and 57 mg g−1 of Eu3+ in pH 2 and pH 1 solutions respectively, highlighting its potential remediation for radionuclides with high charges. SZ-8 not only possesses superior Eu3+ removal capacity under strongly acidic conditions, but also provides a universal synthesis strategy for crystalline zirconium phosphonates with inorganic counterions. [ABSTRACT FROM AUTHOR]

The capture of highly radiotoxic 90Sr from an acidic waste solution during used fuel reprocessing and environmental remediation in a nuclear accident is desirable and challenging. Herein, we show a metal organic framework material (SNU-200) functionalized with an 18-crown-6-ether, whose specific binding site with an excellent affinity toward strontium leads to excellent Sr2+ adsorption capability under acidic conditions. This material exhibits a high adsorption capacity (44.37 mg g−1 at pH = 3), remarkable affinity (Kd = 3.63 × 104 mL g−1) and ultrahigh selectivity in the presence of interfering coexisting ions such as Na+, K+, Cs+, Mg2+, and Ca2+. [ABSTRACT FROM AUTHOR]

Modulated synthesis and isoreticular expansion of Th-MOFs enable the stepwise construction of hierarchical complexes in which porosity and functionality can be fine-tuned, affording new Th-MOFs with a record high void space (74.0%), the largest surface area (3396.5 m2 g−1) among thorium materials, and excellent adsorption capacities toward radioactive iodine. [ABSTRACT FROM AUTHOR]

• New uranyl uptake strategy with combined complexation and photoreduction is shown. • An ultrahigh uranyl uptake capacity not limited by the sorption site is achieved. • Uranyl can be removed completely regardless of its initial concentration. • Uranyl extraction is not affected by the coexisting metal cations. Uranium enrichment is perhaps the most critical chemical process throughout the nuclear fuel cycle including uranium mining, uranium extraction from seawater, used fuel reprocessing and disposal, and environmental contamination remediation. New uranium extraction technology is still highly desirable at current stage, although a variety of extraction methods have been established and developed in the past several decades but all with clear demerits. Herein we present a new uranium extraction strategy with combined ligand complexation and photocatalytic reduction based on postsynthetically functionalized metal-organic frameworks (MOFs). The highly robust and photoactive MOF PCN-222 is modified with phosphono- and amino groups that can capture U(VI) from solution. Upon visible light irradiation, the photo-induced electrons from the MOF host can efficiently reduce U(VI) pre-enriched in MOF, affording neutral uranium species that evacuate the MOF structure and regenerating the active site readily for capturing additional U(VI). This auto-recycled process offers an ultrahigh uranium extraction capacity not limited by the number of adsorption sites and more importantly an extra uranium uptake selectivity over these non-redox-active competing metal cations, and can be utilized for uranium separation over extremely wide uranium concentrations and pH ranges, showing a powerful application potential. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ni-MOF can achieve selectively capture towards Xe/Kr through the window-cage structure with parallel aromatic rings. • The Xe loading capacity of Ni-MOF is the highest among all MOFs without open metal sites. • VdWs Calculations demonstrate the sorption selectivity of Xe over Kr within Ni-MOF originates from a special sandwiched π-Xe-π interaction. Efficient capture and separation of xenon (Xe) and krypton (Kr) from nuclear fuel reprocessing plants is of great significance for the control of discharge of gaseous radioisotopes into the environment. However, due to the similar size and chemically inert spherical properties of Xe/Kr, the discovery of an adsorbent with both high adsorption capacity and high selectivity remains a challenge. Here, we report a microporous MOF (Ni-MOF, [Ni 2 IINiIII(μ 3 -OH)(bdc) 3 (tpt)]·guest) featuring two different cavities with an appropriate triangular hole window size. One is composed of parallel aromatic rings with spacings of approximately 4.3 Å comparable to the kinetic diameter of Xe (4.047 Å), affording excellent binding affinity for Xe while the larger one with narrow pore window provides sufficient space for gas adsorption. The Ni-MOF material exhibits an exceptionally high Xe uptake of 5.43 mmol/g and Xe/Kr selectivity of 7.66 at 298 K and 1 bar. The adsorption capacity is the highest among all MOFs without open-metal-sites. Furthermore, the sorption selectivity of Xe over Kr within Ni-MOF originates from a special sandwiched π-Xe-π interaction revealed by Van der Waals interaction calculations. [ABSTRACT FROM AUTHOR]

With the wide application of nuclear energy and the rapid development of mining, a great quantity of uranium (U(VI)) containing wastewater is inevitably generated. In this work, a facile environmental-friendly coprecipitation method was proposed for the green synthesis of binary layered double hydroxides (Ni–Co LDH W -7), which could be used to efficiently adsorb U(VI) from wastewater. Pseudo-second-order kinetic model and Dubinin-Radushkevich model fitted well with the adsorption of U(VI) on Ni–Co LDH W -7, the maximum adsorption capacity of U(VI) on Ni–Co LDH W -7 was 201.09 mg/g calculated by the Langmuir model. Adsorption equilibrium reached after 30 min, which is a spontaneous and endothermic process. Fourier Transform Infrared Spectrometer (FTIR) and X-ray Photoelectron Spectroscopy (XPS) measurements manifested that the favorable U(VI) extraction on Ni–Co LDH W -7 is mainly ascribed to inner-layer surface electrostatic interaction and complexation, which is dominated by abundant oxygen-containing M-OH and interlayer OH− ions. Briefly, this work provides a facial and environmental-friendly Ni–Co LDH W -7 for removing U(VI) in actual uranium-containing wastewater. [Display omitted] • A facile environmental-friendly coprecipitation method was proposed for green synthesis of Ni–Co LDH W -7. • Adsorption capacity of uranium reached 201.09 mg/g calculated by Langmuir model at pH = 6 and 298 K. • Metal hydroxyl group configuration and the hydroxyl groups contributed to U(VI) binding on Ni–Co LDH W -7. • Ni–Co LDH W -7 showed good stability. [ABSTRACT FROM AUTHOR]