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Herein, we successfully fabricated ultra-small metal nanoparticles into two stable Zr-based metal–organic frameworks via in situ redox reactions between triphenylamine and the corresponding metal ions to afford Pd NPs@1 and Pd NPs@2, which exhibit excellent activity and reusability for Suzuki coupling reactions as heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Unsymmetric sulfides and selenides have great applications in the pharmaceutical field. Herein, we describe the reductive coupling reaction of xanthate esters with sulfur‐containing and selenium‐containing compounds (thio(seleno)sulfonates and disulfides(selenides)) under the nickel‐catalyzed condition. It provides a mild and effective method for the synthesis of unsymmetric sulfides and selenides which has the advantages of mild reaction conditions, high yields and a wide range of substrates. [ABSTRACT FROM AUTHOR]

Herein, we describe a visible-light-mediated selenylation/cyclization reaction of selenium radicals generated from diselenides as radical sources with acrylimide derivatives, which provides a mild and effective method for the synthesis of symmetrical selenosubstituted pyrrolidine-2,5-diones. The described catalytic strategy has the advantages of mild reaction conditions, being metal-free, requiring no additives, easy operation, and having a good substrate range. [ABSTRACT FROM AUTHOR]

A radiochemistry laboratory presents potential radiological hazards due to the handling of multiple radionuclides with various half-lives and modes of radiation emission. To minimize these hazards, appropriate safety management and radiation protection strategies should be in place. The radiochemistry laboratory at Soochow University is one such workplace that handles therapeutic radionuclides, fission products, and actinides in liquid, solid, and gas forms. This work highlights the significance of using safety precautions and radiation protection strategies before conducting experiments in such laboratories. The practical knowledge gained from a case of radioactive contamination is discussed to provide valuable experience for safely conducting radiochemistry experiments. [ABSTRACT FROM AUTHOR]

A photoinduced synthesis of β‐keto thiosulfone/β‐keto selenosulfone by the reaction of α‐bromoacetophenone with thiosulfonate/selenosulfonate under metal‐free and visible light irradiation conditions is developed. Two C−S bonds or one C−S bond and one C−Se bond were constructed simultaneously. [ABSTRACT FROM AUTHOR]

Radiation detection material is a central component of nuclear technology finding applications in many critical fields. Developing a highly radiation-sensitive material that shows a facilely detectable response to ultra-low dosage of radiation is a long-term research target and remains to be a challenge. Previously reported most optimal chemical radiation dosimeter can detect low-dosage X- and γ-ray radiations down to 10−4 Gy. We document here a new photoresponsive coordination polymer showing upgraded radiation detection capabilities with the detection limit on the radiation dose one order of magnitude lower than the previous record. The radiation induced photoluminescence quenching process was elucidated by multiple spectroscopic characterizations. [ABSTRACT FROM AUTHOR]

99Tc contamination at legacy nuclear sites is a serious and unsolved environmental issue. The selective remediation of 99TcO4− in the presence of a large excess of NO3− and SO42− from natural waste systems represents a significant scientific and technical challenge, since anions with a higher charge density are often preferentially sorbed by traditional anion‐exchange materials. We present a solution to this challenge based on a stable cationic metal‐organic framework, SCU‐102 (Ni2(tipm)3(NO3)4), which exhibits fast sorption kinetics, a large capacity (291 mg g−1), a high distribution coefficient, and, most importantly, a record‐high TcO4− uptake selectivity. This material can almost quantitatively remove TcO4− in the presence of a large excess of NO3− and SO42−. Decontamination experiments confirm that SCU‐102 represents the optimal Tc scavenger with the highest reported clean‐up efficiency, while first‐principle simulations reveal that the origin of the selectivity is the recognition of TcO4− by the hydrophobic pockets of the structure. Capturing radioactive species: A robust 3D cationic metal‐organic framework material, SCU‐102, exhibits fast sorption kinetics, large uptake capacity, high distribution coefficient, and a record‐high TcO4− uptake selectivity. The material offers a solution to the long‐term challenge of 99Tc decontamination from complex natural water systems at legacy nuclear sites. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: We present a new method for generating europium oxalate compounds by decomposing of N‐methyl 2‐pyrrolidone in HNO3 media. The reaction exhibits high selectivity towards Eu3+ over UO22+, which suggests that these conditions could be applied to a selective crystallization based separation system for trivalent lanthanides and hexavalent actinides. In this work, a new method for the separation of trivalent Eu3+ and hexavalent UO22+ in initial high‐acidity HNO3 solution is presented. N‐Methyl 2‐pyrrolidone was added in the HNO3 solution where Eu3+ and UO22+ coexisted, then the solution was heated. Eu3+ will react with oxalic acid and dimethylamine produced by N‐methyl 2‐pyrrolidone and form compound NH2(CH3)2[Eu(C2O4)2(H2O)], while UO22+ remains in the solution. This method provide a new strategy for separation of trivalent Eu3+ and hexavalent UO22+. [ABSTRACT FROM AUTHOR]

Abstract: The combination of high atomic number and high oxidation state in UVI materials gives rise to both high X‐ray attenuation efficiency and intense green luminescence originating from ligand‐to‐metal charge transfer. These two features suggest that UVI materials might act as superior X‐ray scintillators, but this postulate has remained substantially untested. Now the first observation of intense X‐ray scintillation in a uranyl–organic framework (SCU‐9) that is observable by the naked eye is reported. Combining the advantage in minimizing the non‐radiative relaxation during the X‐ray excitation process over those of inorganic salts of uranium, SCU‐9 exhibits a very efficient X‐ray to green light luminescence conversion. The luminescence intensity shows an essentially linear correlation with the received X‐ray intensity, and is comparable with that of commercially available CsI:Tl. SCU‐9 possesses an improved X‐ray attenuation efficiency (E>20 keV) as well as enhanced radiation resistance and decreased hygroscopy compared to CsI:Tl. [ABSTRACT FROM AUTHOR]

The example of phase transformation from a centrosymmetric space group at low temperature (LT) to a chiral space group at high temperature (HT) is reported, which was clearly resolved in a single-crystal-to-single-crystal manner in a 3D uranyl(vi) phosphonate compound [TMA][(UO2)2(1,3-pbpH)(1,3-pbpH2)] (1) (TMA+ = tetramethylammonium cation; 1,3-pbpH4 = 1,3-phenylenebis(phosphonic acid)). [ABSTRACT FROM AUTHOR]

Three thorium(iv)-based metal–organic hybrid compounds with 2D layered and 3D framework structures exhibiting graphene-like (6,3) sheet topologies were prepared with linkers with threefold symmetry. These compounds contain rare and relatively anisotropic coordination environments for low-valent actinides that are similar to those often observed for high-valent actinide ions. [ABSTRACT FROM AUTHOR]

The solvothermal reaction of thorium nitrate and tris-(4-carboxylphenyl)phosphine oxide in DMF affords a centrosymmetric porous thorium organic framework compound [Th(TPO)(OH)(H2O)]·8H2O (1). In contrast, the ionothermal reaction of the same reagents in the ionic liquid 1-butyl-2,3-dimethylimidazolium chloride results in the formation of a rare example of a chiral and porous thorium organic framework compound, [C9H17N2][Th(TPO)Cl2]·18H2O (2), which is derived solely from achiral starting materials. The geometries of the Th(iv) centers in compounds 1 and 2 are both atypical for low valent actinides, which can be best described as a ten-coordinate spherical sphenocorona and an irregular muffin, respectively. A large cavity of 17.5 Å (max. face to face) × 8 Å (min. face to face) with a BET surface area of 623 m2 g−1 in compound 2 is observed. The poor stability indicated by thermal gravimetric analysis and the water-resistance test for compound 2 may be due to the unique anisotropic coordination geometry for thorium. Temperature-dependent luminescence studies for both compounds indicate that the trends in the intensity vary as the Th–Th distance and the coordination environments of Th(iv) centers change. [ABSTRACT FROM AUTHOR]

The limited long-term hydrolytic stability of rapidly emerging 3D-extended framework materials (MOFs, COFs, MOPs, etc.) is still one of major barriers for their practical applications as new solid-state electrolytes in fuel cells. To obtain hydrolytically stable materials, two H2PO4−-exchanged 3D inorganic cationic extended frameworks (CEFs) were successfully prepared by a facile anion-exchange method. Both anion-exchanged CEFs (YbO(OH)P and NDTBP) show significantly enhanced proton conductivity when compared with the original materials (YbO(OH)Cl and NDTB) with an increase of up to four orders-of-magnitude, reaching 2.36×10−3 and 1.96×10−2 S cm−1 at 98 % RH and 85 °C for YbO(OH)P and NDTBP, respectively. These values are comparable to the most efficient proton-conducting MOFs. In addition, these two anion-exchanged materials are stable in boiling water, which originates from the strong electrostatic interaction between the H2PO4− anion and the cationic host framework, showing a clear advance over all the acid-impregnated materials (H2SO4@MIL-101, H3PO4@MIL-101, and H3PO4@Tp-Azo) as practical solid-state fuel-cell electrolytes. This work offers a new general and efficient approach to functionalize 3D-extended frameworks through an anion-exchange process and achieves water-stability with ultra-high proton conductivity above 10−2 S cm−1. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) based on zirconium phosphonates exhibit superior chemical stability suitable for applications under harsh conditions. These compounds mostly exist as poorly crystallized precipitates, and precise structural information has therefore remained elusive. Furthermore, a zero-dimensional zirconium phosphonate cluster acting as secondary building unit has been lacking, leading to poor designability in this system. Herein, we overcome these challenges and obtain single crystals of three zirconium phosphonates that are suitable for structural analysis. These compounds are built by previously unknown isolated zirconium phosphonate clusters and exhibit combined high porosity and ultrastability even in fuming acids. SZ-2 possesses the largest void volume recorded in zirconium phosphonates and SZ-3 represents the most porous crystalline zirconium phosphonate and the only porous MOF material reported to survive in aqua regia. SZ-2 and SZ-3 can effectively remove uranyl ions from aqueous solutions over a wide pH range, and we have elucidated the removal mechanism. [ABSTRACT FROM AUTHOR]