Introducing Zirconium Organic Gels for Efficient Radioiodine Gas Removal.

Iodine radioisotope, as one of the most important fission products of uranium, may cause severe damage to human health when it is accidentally discharged into the environment. Hence, efficient removal of radioactive iodine is one of the most critical issues for both used nuclear fuel (UNF) reprocessing and environmental remediation. In this work, three metal-organic gels (MOGs) were introduced for iodine removal. The presented zirconium-based MOGs, namely, CWNU, CWNU-NH2, and CWNU-2NH2, were prepared via moderate solvothermal reactions. These MOGs all exhibit excellent chemical stability and reusability, marked iodine sorption capability, and favorable machinability, which can even rival commercial ones. The sorption capacities are determined to be 3.36, 4.10, and 4.20 g/g, respectively. The increased amount of amino group is considered to be responsible for the elevated iodine sorption capacity and kinetics, as confirmed by combined sorption studies and XPS analysis. The presented work sheds light on the utilization of MOGs for radioiodine capture.

Actinide embedded nearly planar gold superatoms: structural properties and applications in surface-enhanced Raman scattering (SERS).

Planarity is a special property of superatoms, different from atoms. In this work, we predicted a series of nearly planar structures, An@Au6 (An = Ac-1, Th, Pa+1) clusters, using density functional theory (DFT). Calculations of these actinide embedded clusters reveal a 10-electron (1s21p41d4) closed-shell singlet configuration. It is found that all An@Au6 clusters are nearly or purely planar structures with only in-plane two-dimensional occupied superatomic molecular orbitals (SAMOs). In addition, applying them as surface-enhanced Raman scattering (SERS) substrates, the charge-transfer (CT) states at 677 nm (1dmetal-π1*pyridine) can lead to a SERS signal enhancement of 104 for a pyridine-Th@Au6 complex. Our research indicates that actinide embedded nearly planar superatomic clusters have unique optical properties and potential application value.

Cuprous Oxide-Based Cationic Hydrogel by the Integration of Enrichment and Immobilization of Radioiodine (I-, IO3-) in Aqueous Solution.

The efficient capture and immobilization of radioiodine (I-, IO3-) is of great importance in radioactive waste management. Here, a Cu2O-loaded three-dimensional bulk cationic hydrogel composite (Cu2O@CH) was successfully prepared by simple redox reactions and UV photopolymerization, which realized the rapid enrichment and efficient immobilization of I- and IO3-. The adsorption experiments showed that the maximum adsorption capacity of Cu2O@CH for I- in the solution at pH = 3 reached 416.5 mg/g, and the adsorption capacity of IO3- in the solution at pH = 6 could reach 313.4 mg/g. It exhibited extremely fast adsorption kinetics for I- and IO3-. In addition, Cu2O@CH also exhibited efficient I- and IO3- removal from simulated high-level liquid waste. The rapid capture and effective immobilization of radioiodine (I-, IO3-) were realized by the electrostatic interaction of -N+(CH3)3 groups in Cu2O@CH with I- and IO3-, as well as the chemical reactions between Cu2O and I-. The bulk cationic hydrogel composite explored the multifunctional role toward fast, high adsorption capability and easy handling, highlighting its superiority compared to the powder adsorbent, which renders it a potential adsorbent for the removal of radioactive iodine (I-, IO3-) in nuclear wastewater treatment.

Dicylopenta-dien-yl[4-(4-vinyl-benz-yloxy)pyridine-2,6-dicarboxyl-ato]titanium(IV) monohydrate.

The title compound, [Ti(C(5)H(5))(2)(C(16)H(11)NO(5))]·H(2)O, exhibits a titanocene unit coordinated to a styrene-substituted pyridine-2,6-dicarboxyl-ate ligand synthesized for use as a monomer for polymerization or copolymerization yielding metallocene-containing polymers. The compound crystallized as a monohydrate and the solvent water mol-ecule forms strong O-H⋯O hydrogen bonds with the carboxyl-ate O atoms of the Ti complex, which play an important role in the connection of adjacent mol-ecules. In addition, weak inter-molecular C-H⋯O hydrogen bonds also contribute to the crystal packing arrangement.

Controllable Synthesis of Porous Cu-BTC@polymer Composite Beads for Iodine Capture.

The efficient and safe capture of radioactive iodine (129I or 131I) is of great significance in nuclear waste disposal. Here, we report millimeter-scale poly(ether sulfone) composite beads loaded with porous Cu-BTC [Cu3(BTC)2, BTC = 1,3,5-benzenetricarboxylate] (Cu-BTC@PES), prepared by a phase inversion method for the removal of volatile iodine. Three kinds of Cu-BTC@PES composite beads were obtained with different Cu-BTC contents of 48.6, 60.2, and 71.9%, respectively. While maintaining crystallinity, the composite beads exhibited higher I2 vapor adsorption capacity (639 mg/g) in the form of iodine molecules. The iodine absorption up to 260 mg/g and the adsorption was followed Langmuir isotherm and pseudo-second-order kinetic model. Furthermore, the composite beads can still absorb more than 85% of iodine after 3 cycles of regeneration with excellent recyclability. The resulting Cu-BTC@PES composite beads show great potential for the sustainable removal of radioactive iodine.

Preparation and Perfomance of an Aging-Resistant Nanocomposite Film of Binary Natural Polymer-Graphene Oxide.

As one of the materials having a bionic structure, nacrelike layered composites, inspired by their natural hybrid structures, have been studied via a variety of approaches. Graphene oxide (GO), which differed from inert graphene, was used as a new building block because it could be readily chemically functionalized. Rather than natural polymers, synthetic polymers were most commonly used to fabricate nacrelike GO-polymer materials. However, naturally occurring polymers complied more easily with the requirements of biocompatibility, biodegradability, and nontoxicity. Here, a simple solution-casting method was used to mimic natural nacre and fabricate a self-assembled and aging-resistant binary natural polymer, (κ-carrageenan (κ-CAR)-Konjac glucomannan (KGM))-GO nanocomposites, with varying GO concentrations. The investigation results revealed that κ-CAR-KGM and GO mostly self-assemble via the formation of intermolecular hydrogen bonds to form a well-defined layered structure. The mechanical properties of the natural polymer-GO films were improved significantly compared to those of pure natural polymer films. With the addition of 7.5 wt % GO, the tensile strength (TS) and Young's modulus were found to increase by 129.5 and 491.5%, respectively. In addition, the composite films demonstrated high reliability and aging resistance as well as a definite TS after cold and hot shock and ozone aging tests, especially showing a superior ozone resistance. The composite films can potentially be used as biomaterials or packing materials.