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Metal‐organic framework (MOF) based heterostructures, which exhibit enhanced or unexpected functionality and properties due to synergistic effects, are typically synthesized using post‐synthetic strategies. However, several reported post‐synthetic strategies remain unsatisfactory, considering issues such as damage to the crystallinity of MOFs, presence of impure phases, and high time and energy consumption. In this work, we demonstrate for the first time a novel route for constructing MOF based heterostructures using radiation‐induced post‐synthesis, highlighting the merits of convenience, ambient conditions, large‐scale production, and notable time and energy saving. Specifically, a new HKUST‐1@Cu2O heterostructure was successfully synthesized by simply irradiating a methanol solution dispersed of HKUST‐1 with gamma ray under ambient conditions. The copper source of Cu2O was directly derived from in situ radiation etching and reduction of the parent HKUST‐1, without the use of any additional copper reagents. Significantly, the resulting HKUST‐1@Cu2O heterostructure exhibits remarkable catalytic performance, with a catalytic rate constant nearly two orders of magnitude higher than that of the parent HKUST‐1. [ABSTRACT FROM AUTHOR]

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 adsorption of palladium ions from acid nuclear waste solution is crucial for ensuring the safety of vitrification process for radioactive waste. However, the limited stability and selectivity of most current adsorbents hinder their practical applications under strong acid and intense radiation conditions. Herein, to address these limitations, we designed and synthesized an aryl‐ether‐linked covalent organic framework (COF‐316‐DM) grafted dimethylthiocarbamoyl groups on the pore walls. This unique structure endows COF‐316‐DM with high stability and exceptional palladium capture capacity. The robust polyarylether linkage enables COF‐316‐DM to withstand irradiation doses of 200 or 400 kGy of β/γ ray. Furthermore, COF‐316‐DM demonstrates fast adsorption kinetics, high adsorption capacity (147 mg g−1), and excellent reusability in 4 M nitric acid. Moreover, COF‐316‐DM exhibits remarkable selectivity for palladium ions in the presence of 17 interference ions, simulating high level liquid waste scenario. The superior adsorption performance can be attributed to the strong binding affinity between the thioamide groups and Pd2+ ions, as confirmed by the comprehensive analysis of FT‐IR and XPS spectra. Our findings highlight the potential of COFs with robust linkers and tailored functional groups for efficient and selective capture of metal ions, even in harsh environmental conditions. [ABSTRACT FROM AUTHOR]

Halide perovskites (HPs) recently have emerged as one class of competitive scintillators for X‐ray detection and imaging owing to its high quantum efficiency, short decay time, superior X‐ray absorption capacity, low cost, and ease of crystal growth. The tunable structure and versatile chemical compositions of halide perovskites provide distinguishable advantages over traditional inorganic scintillators for optimizing scintillation performance. Since the first observation of the scintillation phenomenon in HPs, substantial efforts have been devoted to expanding the inventory of HP scintillators and regulating material properties. Understanding the relationship between the structure and scintillation properties of HP scintillators is essential for developing materials with improved X‐ray detection and imaging capacities. This review summarizes strategies for improving the light yield of HP scintillators and provides a roadmap for improving the X‐ray imaging performance. Additionally, methods for controlling the light propagation direction in HP scintillators are highlighted for improving X‐ray imaging resolution. Finally, we highlight the current challenge in HP scintillators and provide a perspective on the future development of this emerging scintillator. [ABSTRACT FROM AUTHOR]

The development of high‐performance X‐ray detectors requires scintillators with fast decay time, high light yield, stability, and X‐ray absorption capacity, which are difficult to achieve in a single material. Here, we present the first example of a lanthanide chalcogenide of LaCsSiS4 : 1 % Ce3+ that simultaneously integrates multiple desirable properties for an ideal scintillator. LaCsSiS4 : 1 % Ce3+ demonstrates a remarkably low detection limit of 43.13 nGyair s−1 and a high photoluminescence quantum yield of 98.24 %, resulting in a high light yield of 50480±1441 photons/MeV. Notably, LaCsSiS4 : 1 % Ce3+ exhibits a fast decay time of only 29.35±0.16 ns, making it one of the fastest scintillators among all lanthanide‐based inorganic scintillators. Furthermore, this material shows robust radiation and moisture resistance, endowing it with suitability for chemical processing under solution conditions. To demonstrate the X‐ray imaging capacity of LaCsSiS4 : 1 % Ce3+, we fabricated a flexible X‐ray detector that achieved a high spatial resolution of 8.2 lp mm−1. This work highlights the potential of lanthanide chalcogenide as a promising candidate for high‐performance scintillators. [ABSTRACT FROM AUTHOR]

Periodically arranging coordination‐distinct actinides into one crystalline architecture is intriguing but of great synthetic challenge. We report a rare example of a heterobimetallic actinide metal–organic framework (An‐MOF) by a unique reaction‐induced preorganization strategy. A thorium MOF (SCU‐16) with the largest unit cell among all Th‐MOFs was prepared as the precursor, then the uranyl was precisely embedded into the MOF precursor under oxidation condition. Single crystal of the resulting thorium‐uranium MOF (SCU‐16‐U) shows that a uranyl‐specific site was in situ induced by the formate‐to‐carbonate oxidation reaction. The heterobimetallic SCU‐16‐U exhibits multifunction catalysis properties derived from two distinct actinides. The strategy proposed here offers a new avenue to create mixed‐actinide functional material with unique architecture and versatile functionality. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The second example of tetravalent plutonium carboxyl‐based organic framework, 242Pu(OH)[PO[(C6H4)COO]3]·H2O, termed as PuTPO (TPO = tris(4‐carboxylphenyl)‐phosphineoxide), was reported in this work. A series of characterizations of PuTPO, such as X‐ray crystallography and solid‐state UV‐Vis‐NIR spectroscopy, were carried out to expatiate its structure and physicochemical properties. PuTPO is constructed by dimers of the plutonium‐oxygen subunit of [Pu2O16]. Characteristic peaks located at approximately 1100 nm can be considered to be the fingerprint peaks of tetravalent plutonium. While PuTPO can maintain high crystallinity within several months after synthesis, it exhibits a radiation‐induced swelling effect probed by the expansion of cell parameter of b axis after self‐irradiation from α‐decay of 242Pu. This result enriches the inventory of tetravalent plutonium compounds and provides an insight into the irradiation resistance of metal‐organic frameworks. [ABSTRACT FROM AUTHOR]

Although examples of multiple bonds between actinide elements and main‐group elements are quite common, studies of the multiple bonds between actinide elements and transition metals are extremely rare owing to difficulties associated with their synthesis. Here we report the first example of molecular uranium complexes featuring a cis‐[M→→ ${{\rm{ \mathbin{{\stackrel{\textstyle\rightarrow} { {\smash{\rightarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ U←← ${{\rm{ \mathbin{{\stackrel{\textstyle\leftarrow} { {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ M] core (M=Rh, Ir), which exhibits an unprecedented arrangement of two M→→ ${{\rm{ \mathbin{{\stackrel{\textstyle\rightarrow} { {\smash{\rightarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ U double dative bond linkages to a single U center. These complexes were prepared by the reactions of chlorine‐bridged heterometallic complexes [{U{N(CH3)(CH2CH2NPiPr2)2}(Cl)2[(μ‐Cl)M(COD)]2}] (M=Rh, Ir) with MeMgBr or MeLi, a new method for the construction of species with U−M multiple bonds. Theoretical calculations including dispersion confirmed the presence of two U←← ${{\rm{ \mathbin{{\stackrel{\textstyle\leftarrow} { {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ M double dative bonds in these complexes. This study not only enriches the U←← ${{\rm{ \mathbin{{\stackrel{\textstyle\leftarrow} { {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ M multiple bond chemistry, but also provides a new opportunity to explore the bonding of actinide elements. [ABSTRACT FROM AUTHOR]

The exceptional photophysical properties of 3D organic–inorganic lead halide hybrids (OILHs) endow their significant potential for usage in optoelectronics, which has sparked intense research on novel 3D OILHs and associated applications. However, constructing new 3D OILHs based on large organic cations suffers from tough challenges due to the limitation of the Goldschmidt tolerance factor rule, let alone further explorations of their practical applications. Herein, a brand‐new 3D lead chloride hybrid, (1MPZ)Pb4Cl10·H2O (1, 1MPZ = 1‐methylpiperazine) is reported, featuring a dense 3D lead chloride framework made of the corner‐, edge‐, and face‐shared lead chloride polyhedra. 1 presents a broadband white light emission with a large Stokes shift and a nanosecond photoluminescence lifetime, which originates from radiative recombination of self‐trapped excitons (STEs) induced by the highly distorted structure. Such a reabsorption‐free and fast‐decayed STEs emission coupling with the dense 3D architecture further enables 1 with effective X‐ray scintillation with good sensitivity. Impressively, 1 also shows superior environmental and radiation stability. This study provides a new 3D OILH with appealing luminescence, not only expanding the 3D OILH family but also inspiring the exploitation of their optoelectronic applications. [ABSTRACT FROM AUTHOR]

Metal organic frameworks (MOFs) are a distinct family of crystalline porous materials finding extensive applications. Their synthesis often requires elevated temperature and relatively long reaction time. We report here the first case of MOF synthesis activated by high‐energy (1.5 MeV) electron beam radiation from a commercially available electron‐accelerator. Using ZIF‐8 as a representative for demonstration, this type of synthesis can be accomplished under ambient conditions within minutes, leading to energy consumption about two orders of magnitude lower than that of the solvothermal condition. Interestingly, by controlling the absorbed dose in the synthesis, the electron beam not only activates the formation reaction of ZIF‐8, but also partially etches the material during the synthesis affording a hierarchical pore architecture and highly crystalline ZnO nanoparticles on the surface of ZIF‐8. This gives rise to a new strategy to obtain MOF@metal oxide heterostructures, finding utilities in photocatalytic degradation of organic dyes. [ABSTRACT FROM AUTHOR]

Scintillators display radioluminescent properties when irradiated by high‐energy photons and therefore play an essential role in radiation detection. The current inventory of scintillators is overwhelmingly represented by achiral structures, where the radioluminescence propagates isotropically after generation. Herein, we demonstrate that chiral perovskites of (R‐3AP)PbBr3Cl⋅H2O (R‐3APP) and (S‐3AP)PbBr3Cl⋅H2O (S‐3APP) emerge as a new type of scintillator displaying a distinct property of circularly polarized radioluminescence (CPRL). A high quantum yield of 27.6 %, high luminescence dissymmetric factors (glum) of 4×10−2, and high X‐ray absorption coefficients were observed for these compounds. As proof of concept, we fabricated a polarized scintillator pair by assembling chiral scintillator crystals, which provides a new strategy to attenuate optical crosstalk between the scintillators by precisely controlling the radioluminescence propagation and improves the X‐ray imaging quality at the boundary region. [ABSTRACT FROM AUTHOR]

Multi‐level memory can greatly improve information density, so it has been widely studied. In this study, a carbazole‐based donor–acceptor polymer poly[2,7‐9‐(heptadecan‐9‐yl)‐9H‐carbazole‐alt‐7H‐benzimidazo[2,1‐a]benz[de]isoquinolin‐7‐one] (PCz‐BB) is synthesized, which exhibits flash‐type ternary memory behavior. Further, CdS nanoparticles (NPs) are embedded into the prepared polymer to enhance the storage performance. The current–voltage (I–V) characteristics of memory devices based on PCz‐BB:CdS composites and the effect of the embedding ratio of CdS NPs on the memory devices are studied. It is verified that the ON2/ON1/OFF current ratios of the devices at low CdS embedding concentrations are improved, and the threshold voltages are also reduced. The memory device based on the optimal embedding concentration (3 wt% CdS) exhibits a high ON2/ON1/OFF current ratio of 18631:72:1, a low threshold voltage of −0.40/−1.20 V, and excellent stability. The mechanism of resistive switching is explained by the theory of charge traps and conductive filaments. This work provides a new avenue for high‐performance multi‐level organic electrical storage materials. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The environmental contamination of uranium will occur in scenarios such as nuclear accidents and leakage from nuclear waste storage sites, which eventually leads to the internal uranium exposure of people, causing consequential injuries of renal failure, osteosarcoma, etc. The development of uranyl specific chelating agents that could sequester uranium in vivo is in urgent need and is important for the safe and efficient development of nuclear industry. Metal organic frameworks (MOFs) already serve as efficient uranium depletion materials in solutions of a wide range of pH and ionic strength for nuclear fuel recycling, uranium extraction from seawater, as well as environmental decontamination. Herein, a chromium‐based nano‐metal organic framework (nano‐MOF) functionalized interiorly with 3,2‐HOPO ligands, MIL‐101‐HOPO, is rationally synthesized. In vitro adsorption experiments show that MIL‐101‐HOPO exhibits high adsorption selectivity and fast adsorption kinetics for uranyl. The results of in vivo uranyl decorporation assays reveal that MIL‐101‐HOPO with the decoration of HOPO ligands on the interior wall exhibits significantly increased uranyl removal ratio in kidneys comparing to the pristine nMOFs, and is more effective than the clinically used ZnNa3‐DTPA. All those results corroborate the interior functionalization of MOFs as an efficient strategy to develop promising uranyl decorporation agents. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: We reported the synthesis, single crystal structure, and solid‐state UV‐Vis‐NIR spectroscopy of a new transplutonium metal‐organic framework (MOFs), Am(H2O)[PO[(C6H4)COO]3], denoted as AmTPO (TPO = tris(4‐carboxylphenyl)‐phosphineoxide). AmTPO forms a three‐dimensional metal−organic framework structure with americium dimers as the secondary building unit. Clear 5f → 5f transitions attributed to trivalent americium was observed in the absorption spectrum of AmTPO ranging from 300 to 1200 nm. Notably, AmTPO can maintain the crystallinity with no observable structural degradation within several months after being synthesized, revealing a long‐term radiation resistance of this structure and the potential application of MOFs as a platform for nuclear waste disposal. [ABSTRACT FROM AUTHOR]

Luminescent covalent organic frameworks (COFs) find promising applications in chemical sensing, photocatalysis, and optoelectronic devices, however, the majority of COFs are non or weakly emissive owing to the aggregation‐caused quenching (ACQ) or the molecular thermal motion‐based energy dissipation. Here, we report a previously unperceived approach to improve luminescence performance of COFs by introducing isotope effect, which is achieved through substitution of hydrogen from high‐frequency oscillators X‐H (X=O, N, C) by heavier isotope deuterium. Combining the "bottom‐up" and in situ deuteration methods generates the first deuterated COF, which exhibits an impressively 19‐fold enhancement in quantum yield over that of the non‐deuterated counterpart. These results are interpreted by theoretical calculations as the consequence of slower C/N‐D and OD⋅⋅⋅O vibrations that impede the nonradiative deactivation process. The proposed strategy is proved applicable to many other types of emissive COFs. [ABSTRACT FROM AUTHOR]

Halide hybrid perovskites are attracting considerable attention as highly promising candidates for directly sensing X‐ray radiation, but it is challenging to realize passive X‐ray detection without an external power supply. However, the bulk photovoltaic effect (BPVE) in ferroelectrics promotes the independent separation of photoexcited carriers. Herein, by dimensionality reconstruction of a pure‐two‐dimensional (P‐2D) monolayered perovskite (CH3OC3H9N)2PbBr4, we obtained a quasi‐two‐dimensional (Q‐2D) ferroelectric (CH3OC3H9N)2CsPb2Br7. Converting P‐2D into Q‐2D perovskite stimulates a significant BPVE associated with robust ferroelectricity, as well as an enhanced mobility lifetime product. These features show the potential of the first passive X‐ray detector based on ferroelectrics with an impressive sensitivity up to 410 μC Gy−1 cm−2 at zero bias, which is even superior to the value of the state‐of‐the‐art α‐Se detector operated at relatively high bias. [ABSTRACT FROM AUTHOR]

Low‐valent uranium‐element multiple bond complexes remain scarce, though there is burgeoning interest regarding to their bonding and reactivity. Herein, isolation of a uranium(III)‐carbon double bond complex [(Cp*)2U(CDP)](BPh4) (1) comprising a tridentate carbodiphosphorane (CDP) was reported for the first time. Oxidation of 1 afforded the corresponding U(IV) complex [(Cp*)2U(CDP)](BPh4)2 (2). The distance between U and C in 2 is 2.481 Å, indicating the existence of a typical U=C double bond, which is further confirmed by quantum chemical calculations. Bonding analysis suggested that the CDP also serves as both σ‐ and π‐donor in complex 1, though a longer U−C bond (2.666(3) Å) is observed. It implies that 1 is the first isolable mononuclear uranium(III) carbene complex. Moreover, these results suggest that CDPs are promising ligands to establish other low‐valent f‐block metal‐carbon multiple bond complexes. [ABSTRACT FROM AUTHOR]

Zeolites are a well‐known family of microporous aluminosilicate crystals with a wide range of applications. Their industrial synthetic method under hydrothermal condition requires elevated temperature and long crystallization time and is therefore quite energy‐consuming. Herein, we utilize high‐energy electron beam irradiation generated by an industrial accelerator as a distinct type of energy source to activate the formation reaction of Na‐A zeolite. The initial efforts afford an attractive reaction process that can be achieved under ambient conditions and completed within minutes with almost quantitative yield, leading to notable energy saving of one order of magnitude compared to the hydrothermal reaction. More importantly, electron beam irradiation simultaneously exhibits an etching effect during the formation of zeolite generating a series of crystal defects and additional pore windows that can be controlled by irradiation dose. These observations give rise to significantly enhanced surface area and heavy metal removal capabilities in comparison with Na‐A zeolite synthesized hydrothermally. Finally, we show that this method can be applied to many other types of zeolites. [ABSTRACT FROM AUTHOR]

We disclose the intrinsic semiconducting properties of one of the largest mixed‐valent uranium clusters, [H3O+][UV(UVIO2)8(μ3‐O)6(PhCOO)2(Py(CH2O)2)4(DMF)4] (Ph=phenyl, Py=pyridyl, DMF=N,N‐dimethylformamide) (1). Single‐crystal X‐ray crystallography demonstrates that UV center is stabilized within a tetraoxo core surrounded by eight uranyl(VI) pentagonal bipyramidal centers. The oxidation states of uranium are substantiated by spectroscopic data and magnetic susceptibility measurement. Electronic spectroscopy and theory corroborate that UV species serve as electron donors and thus facilitate 1 being a n‐type semiconductor. With the largest effective atomic number among all reported radiation‐detection semiconductor materials, charge transport properties and photoconductivity were investigated under X‐ray excitation for 1: a large on‐off ratio of 500 and considerable charge mobility lifetime product of 2.3×10−4 cm2 V−1, as well as a high detection sensitivity of 23.4 μC Gyair−1 cm−2. [ABSTRACT FROM AUTHOR]

As one of most problematic radionuclides, technetium‐99, mainly in the form of anionic pertechnetate (TcO4−), exhibits high environmental mobility, long half‐life, and radioactive hazard. Due to low charge density and high hydrophobicity for this tetrahedral anion, it is extremely difficult to recognize it in water. Seeking efficient and selective recognition method for TcO4− is still a big challenge. Herein, a new water‐stable cationic metal‐organic framework (ZJU‐X8) was reported, bearing tetraphenylethylene pyrimidine‐based aggregation‐induced emission (AIE) ligands and attainable silver sites for TcO4− detection. ZJU‐X8 underwent an obvious spectroscopic change from brilliant blue to flavovirens and exhibited splendid selectivity towards TcO4−. This uncommon fluorescent recognition mechanism was well elucidated by batch sorption experiments and DFT calculations. It was found that only TcO4− could enter into the body of ZJU‐X8 through anion exchange whereas other competing anions were excluded outside. Subsequently, after interaction between TcO4− and silver ions, the electron polarizations from pyrimidine rings to Ag+ cations significantly lowered the energy level of the π* orbital and thus reduced the π–π* energy gap, resulting in a red‐shift in the fluorescent spectra. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Two new uranium(VI) phosphonate compounds, namely K8[N(C2H5)4]2(UO2)17(H2O)4[CH2(PO3)2]8[CH2(PO3)(PO3H)]4‧16(H2O) (1) and [N(C2H5)4]4(H3O)2(UO2)10[CH2(PO3)2]5[CH2(PO3)(PO3H)]2‧10H2O (2), have been synthesized under mild hydro/solvothermal condition. The structural analysis of the two compounds reveals that they both contain all three typical coordination geometries of the U(VI) ions, including UO6 tetragonal, UO7 pentagonal, and UO8 hexagonal bipyramids. Moreover, compound 1 displays a temperature‐induced single crystal to single crystal phase transformation as confirmed by the Single‐crystal X‐ray diffraction data collected at different temperatures. Temperature‐dependent fluorescence spectra presented herein illustrate the perturbation of the electronic structure of uranyl centers. [ABSTRACT FROM AUTHOR]

Activation of dinitrogen (N2, 78 %) and dioxygen (O2, 21 %) has fascinated chemists and biochemists for decades. The industrial conversion of N2 into ammonia requires extremely high temperatures and pressures. Herein we report the first example of N2 and O2 cleavage by a uranium complex, [N(CH2CH2NPiPr2)3U]2(TMEDA), under ambient conditions without an external reducing agent. The N2 triple bond breaking implies a UIII–PIII six‐electron reduction. The hydrolysis of the N2 reduction product allows the formation of ammonia or nitrogen‐containing organic compounds. The interaction between UIII and PIII in this molecule allows an eight‐electron reduction of two O2 molecules. This study establishes that the combination of uranium and a low‐valent nonmetal is a promising strategy to achieve a full N2 and O2 cleavage under ambient conditions, which may aid the design of new systems for small molecules activation. [ABSTRACT FROM AUTHOR]

A wide range of tunability in the physical parameters of a semiconductor used for X‐ray detection is desirable to achieve targeted performance optimization. However, in a dense‐phase semiconductor, fine‐tuning one parameter often leads to unwanted changes in other parameters. Herein, the intrinsic openness in an open‐framework semiconductor has been confirmed, for the first time, to be a key structural factor that weakens the mutual exclusivity of the adjustable physical parameters owing to a non‐linear control mechanism. The controllable doping of S in a zeolitic In–Se host results in an optimal balance between resistivity, band gap, and carrier mobility, which finally results in an excellent X‐ray detector with a high figure of merit for the mobility–lifetime product (7.12×10−4 cm2 V−1); this value is superior to that of a commercial α‐Se detector. The current strategy of choosing open‐framework semiconductor materials opens a new window for targeting high‐performance X‐ray detection. [ABSTRACT FROM AUTHOR]

Radio‐photoluminescence (RPL) materials display a distinct radiation‐induced permanent luminescence center, and therefore find application in the detection of ionizing radiation. The current inventory of RPL materials, which were discovered by serendipity, has been limited to a small number of metal‐ion‐doped inorganic materials. Here we document the RPL of a metal–organic framework (MOF) for the first time: X‐ray induced free radicals are accumulated on the organic linker and are subsequently stabilized in the conjugated fragment in the structure, while the metal center acts as the X‐ray attenuator. These radicals afford new emission features in both UV‐excited and X‐ray excited luminescence spectra, making it possible to establish linear relationships between the radiation dose and the normalized intensity of the new emission feature. The MOF‐based RPL materials exhibit advantages in terms of the dose detection range, reusability, emission stability, and energy threshold. Based on a comprehensive electronic structure and energy diagram study, the rational design and a substantial expansion of candidate RPL materials can be anticipated. [ABSTRACT FROM AUTHOR]

Semiconductive metal–organic frameworks (MOFs) have emerged in applications such as chemical sensors, electrocatalysts, energy storage materials, and electronic devices. However, examples of semiconductive MOFs within flexible electronics have not been reported. We present flexible X‐ray detectors prepared by thermoplastic dispersal of a semiconductive MOF (SCU‐13) through a commercially available polymer, poly(vinylidene fluoride). The flexible detectors exhibit efficient X‐ray‐to‐electric current conversion with enhanced charge‐carrier mobility and low trap density compared to pelleted devices. A high X‐ray detection sensitivity of 65.86 μCGyair−1 cm−2 was achieved, which outperforms other pelleted devices and commercial flexible X‐ray detectors. We demonstrate that the MOF‐based flexible detectors can be operated at multiple bending angles without a deterioration in detection performance. As a proof‐of‐concept, an X‐ray phase contrast under bending conditions was constructed using a 5×5 pixelated MOF‐based imager. [ABSTRACT FROM AUTHOR]

Two new uranylzinc germanates, (UO2)4(ZnO)(Ge2O7)2·(H3O)4 (UZG‐1) and (UO2)3[Zn(H2O)3](GeO4)2 (UZG‐2), have been prepared and characterized. Both compounds are constructed from anionic uranyl germanate open‐frameworks embedded with Zn2+ cations in the voids via rather unusual 3d‐5f heterometallic cation‐cation interactions. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) is a bottleneck process for water splitting and finding highly efficient, durable, low‐cost, and earth‐abundant electrocatalysts is still a major challenge. Here a sulfur‐treated Fe‐based metal–organic‐framework is reported as a promising electrocatalyst for the OER, which shows a low overpotential of 218 mV at the current density of 10 mA cm−2 and exhibits a very low Tafel slope of 36.2 mV dec−1 at room temperature. It can work on high current densities of 500 and 1000 mA cm−2 at low overpotentials of 298 and 330 mV, respectively, by keeping 97% of its initial activity after 100 h. Notably, it can achieve 1000 mA cm−2 at 296 mV with a good stability at 50 °C, fully fitting the requirements for large‐scale industrial water electrolysis. The high catalytic performance can be attributed to the thermocatalytic processes of H+ capture by –SO3 groups from *OH or *OOH species, which cascades to the electrocatalytic pathway and then significantly reduces the OER overpotentials. [ABSTRACT FROM AUTHOR]

Scintillators are a unique class of luminescent materials with specific applications towards radiation detection. The emitters within state‐of‐the‐art scintillators are mostly limited to bismuth, cerium, europium, thallium, lead, tungsten, etc. A shared feature of these elements is the relatively high atomic number, which is responsible for high radiation stopping power and radiation‐induced luminescence. Searching for new scintillating materials is an essential target aiming at specific applications. In this Concept article, we will discuss our recent works on the topic of "uranyl‐bearing scintillators". As a virgin territory in this field, uranyl‐bearing scintillators show intrinsic merits for designing new materials with X‐ray detection capability, that is, the large photoelectric cross‐section, high X‐ray attenuation efficiency, and high crystal density. In addition, we also present challenges in the further development of the uranyl‐bearing scintillators. [ABSTRACT FROM AUTHOR]

A systematic investigation of uranyl borates under different synthetic conditions resulted in five new 2D compounds, namely, (H3O)[(UO2)(BO3)], Li[(UO2)(BO3)]·(H2O), α‐K4[(UO2)5(BO3)2O4], β‐K4[(UO2)5(BO3)2O4] and K2.5[(UO2)5(BO3)2O2.5(OH)1.5]·(H2O)2.5. (H3O)[(UO2)(BO3)] and Li[(UO2)(BO3)]·(H2O) were obtained from hydrothermal reactions at 220 °C using the same mineralizer. Both materials possess the uranophane sheet topology with different symmetry of the unit cells. In the structure of (H3O)[(UO2)(BO3)] and Li[(UO2)(BO3)]·(H2O), UO7 pentagonal bipyramids share edges and vertexes with four BO3 planar triangles. α‐K4[(UO2)5(BO3)2O4] and β‐K4[(UO2)5(BO3)2O4] are polytypes. α‐K4[(UO2)5(BO3)2O4] was synthesized from a high‐temperature solid‐state reaction under ambient pressure; whereas β‐K4[(UO2)5(BO3)2O4] was obtained from a high‐temperature/high‐pressure (HT/HP) reaction. Both structures have an identical anion topology, but β‐K4[(UO2)5(BO3)2O4] crystallizes in space group with higher symmetry. In K2.5[(UO2)5(BO3)2O2.5(OH)1.5]·(H2O)2.5, which was obtained from a hydrothermal reaction, UO7 polyhedra share vertexes and edges with two independent BO3 triangles, forming the most complex uranyl borate layers among all five compounds. The different synthetic routes, novel topologies, thermal behavior and Raman spectra are discussed. [ABSTRACT FROM AUTHOR]

The design and synthesis of uranium sorbent materials with high uptake efficiency, capacity and selectivity, as well as excellent hydrolytic stability and radiation resistance remains a challenge. Herein, a polyoxometalate (POM)–organic framework material (SCU‐19) with a rare inclined polycatenation structure was designed, synthesized through a solvothermal method, and tested for uranium separation. Under dark conditions, SCU‐19 can efficiently capture uranium through ligand complexation using its exposed oxo atoms and partial chemical reduction from UVI to UIV by the low‐valent Mo atoms in the POM. An additional UVI photocatalytic reduction mechanism can occur under visible light irradiation, leading to a higher uranium removal without saturation and faster sorption kinetics. SCU‐19 is the only uranium sorbent material with three distinct sorption mechanisms, as further demonstrated by X‐ray photoelectron spectroscopy (XPS) and X‐ray absorption near edge structure (XANES) analysis. [ABSTRACT FROM AUTHOR]

Designability is an attractive feature for metal–organic frameworks (MOFs) and essential for reticular chemistry, and many ideas are significantly useful in the carboxylate system. Bi‐, tri‐, and tetra‐topic phosphonate ligands are used to achieve framework structures. However, an efficient method for designing phosphonate MOFs is still on the way, especially for uranyl phosphonates, owing to the complicated coordination modes of the phosphonate group. Uranyl phosphonates prefer layer or pillar‐layered structures as the topology extension for uranyl units occurs in the plane perpendicular to the linear uranium‐oxo bonds and phosphonate ligands favor the formation of compact structures. Therefore, an approach that can construct three‐dimensional (3D) uranyl phosphonate MOFs is desired. In this paper, a sterically hindered phosphonate ligand method (SHPL) is described and is successfully used to achieve 3D framework structures of uranyl phosphonates. Four MOF compounds ([AMIM]2(UO2)(TppmH4)⋅H2O (UPF‐101), [BMMIM]2(UO2)3(TppmH4)2⋅H2O (UPF‐102), [Py14]2(UO2)3(TppmH4)2⋅3 H2O (UPF‐103), and [BMIM](UO2)3(TppmH3)F2⋅2 H2O (UPF‐104); [AMIM]=1‐allyl‐3‐methylimidazolium, [BMMIM]=1‐butyl‐2,3‐dimethylimidazolium, [Py14]=N‐butyl‐N‐methylpyrrolidinium, and [BMIM]=1‐butyl‐3‐methylimidazolium) are obtained by ionothermal synthesis, with zero‐dimensional nodes of uranyl phosphonates linked by steric tetra‐topic ligands, namely tetrakis[4‐(dihyroxyphosphoryl)phenyl]methane (TppmH8), to give 3D framework structures. Characterization by PXRD, UV/Vis, IR, Raman spectroscopy, and thermogravimetry (TG) were also performed. [ABSTRACT FROM AUTHOR]

Flexible X-Ray Detector, Lanthanide Chalcogenide Scintillator, Luminescence, X-Ray Imaging Keywords: Flexible X-Ray Detector; Lanthanide Chalcogenide Scintillator; Luminescence; X-Ray Imaging EN Flexible X-Ray Detector Lanthanide Chalcogenide Scintillator Luminescence X-Ray Imaging 1 1 1 08/10/23 20230814 NES 230814 B Scintillators b . Frontispiece: Emergence of a Lanthanide Chalcogenide as an Ideal Scintillator for a Flexible X-ray Detector. [Extracted from the article]

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]

Abstract: Actinide based metal–organic frameworks (MOFs) are unique not only because compared to the transition‐metal and lanthanide systems they are substantially less explored, but also owing to the uniqueness of actinide ions in bonding and coordination. Now a 3D thorium–organic framework (SCU‐11) contains a series of cages with an effective size of ca. 21×24 Å. Th4+ in SCU‐11 is 10‐coordinate with a bicapped square prism coordination geometry, which has never been documented for any metal cation complexes. The bicapped position is occupied by two coordinated water molecules that can be removed to afford a very unique open Th4+ site, confirmed by X‐ray diffraction, color change, thermogravimetry, and spectroscopy. The degassed phase (SCU‐11‐A) exhibits a Brunauer–Emmett–Teller surface area of 1272 m2 g−1, one of the highest values among reported actinide materials, enabling it to sufficiently retain water vapor, Kr, and Xe with uptake capacities of 234 cm3 g−1, 0.77 mmol g−1, 3.17 mmol g−1, respectively, and a Xe/Kr selectivity of 5.7. [ABSTRACT FROM AUTHOR]

The present study sheds some light on the long‐standing debate concerning the coordination properties between uranyl ions and the amidoxime ligand, which is a key ingredient for achieving efficient extraction of uranium. Using X‐ray absorption fine structure combined with theoretical simulation methods, the binding mode and bonding nature of a uranyl–amidoxime complex in aqueous solution were determined for the first time. The results show that in a highly concentrated amidoxime solution the preferred binding mode between UO22+ and the amidoxime ligand is η2 coordination with tris‐amidoximate species. In such a uranyl–amidoximate complex with η2 binding motif, strong covalent interaction and orbital hybridization between U 5f/6d and (N, O) 2p should be responsible for the excellent binding ability of the amidoximate ligand to uranyl. The study was performed directly in aqueous solution to avoid the possible binding mode differences caused by crystallization of a single‐crystal sample. This work also is an example of the simultaneous study of local structure and electronic structure in solution systems using combined diagnostic tools. [ABSTRACT FROM AUTHOR]

Abstract: Controllable and repeatable crystal imperfection modulation engineering (CIME) is important for the development of semiconductor science and technology. However, for wide band gap semiconductors (WBGSs), there still lacks universal and reliable CIME. Here, based on the general idea of chemical composition complete expression design, a well‐designed, repeatable, and feasible CIME for ZnO is introduced, making free modulation of carrier in WBGS become possible. Briefly, this extraordinary CIME is dominated by two innovative procedures: an electrochemical doping and a strong oxidizing atmosphere annealing. The proposed CIME is a repeatable and universal carrier modulation project, which holds technological promise for various WBGS‐based semiconductor devices. Benefiting from this CIME, an α particle detector which operating at a high electric field of 107 V cm−1 can be fabricated successfully. [ABSTRACT FROM AUTHOR]

Precise detection of low-dose X- and γ-radiations remains a challenge and is particularly important for studying biological effects under low-dose ionizing radiation, safety control in medical radiation treatment, survey of environmental radiation background, and monitoring cosmic radiations. We report here a photoluminescent uranium organic framework, whose photoluminescence intensity can be accurately correlated with the exposure dose of X- or γ-radiations. This allows for precise and instant detection of ionizing radiations down to the level of 10−4 Gy, representing a significant improvement on the detection limit of approximately two orders of magnitude, compared to other chemical dosimeters reported up to now. The electron paramagnetic resonance analysis suggests that with the exposure to radiations, the carbonyl double bonds break affording oxo-radicals that can be stabilized within the conjugated uranium oxalate-carboxylate sheet. This gives rise to a substantially enhanced equatorial bonding of the uranyl(VI) ions as elucidated by the single-crystal structure of the γ-ray irradiated material, and subsequently leads to a very effective photoluminescence quenching through phonon-assisted relaxation. The quenched sample can be easily recovered by heating, enabling recycled detection for multiple runs. [ABSTRACT FROM AUTHOR]

It is shown that UVO2+ ions can reside at UVIO22+ lattice sites during mild reduction and crystallization process under solvothermal conditions, yielding a complicated and rare mixed-valent uranium phosphonate compound that simultaneously contains UIV, UV, and UVI. The presence of uranium with three oxidation states was confirmed by various characterization techniques, including X-ray crystallography, X-ray photoelectron, electron paramagnetic resonance, FTIR, UV/Vis-NIR absorption, and synchrotron radiation X-ray absorption spectroscopy, and magnetism measurements. [ABSTRACT FROM AUTHOR]

Cooperative performance of mixed-valent Eu2+/Eu3+ in single-compound phosphors offers significant advantages in color rendering and luminescence efficiency, but their synthesis is challenging because of Eu2+ oxidation. Using the tunable nature of the metal-ion nodes in metal-organic frameworks (MOFs), we present an in situ reduction and crystallization route for preparing MOFs and doping Eu2+/Eu3+ with a controlled ratio. These materials exhibit rich photoluminescence, including intrinsic- and sensitized-emissions of Eu2+ and Eu3+, and long-lived luminescence from charge transfer. Color rendering can be easily achieved by fine-tuning the valence states of Eu. A linear relation between temperature and the intensity ratio of Eu2+/Eu3+ emissions provides outstanding properties for applications as self-calibrated luminescent thermometers with a wide working temperature range. Further incorporation of Tb3+ into the MOFs results in white light, utilizing all Eu2+,Tb3+, and Eu3+ emissions in a single crystalline lattice. [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]

Two‐electron oxidative addition is one of the most important elementary reactions for d‐block transition metals but it is uncommon for f‐block elements. Here, we report the first examples of intermolecular oxidative addition of E−H (E=C, N) bonds to uranium(II) centers. The transient U(II) species was formed in‐situ by reducing a heterometallic cluster featuring U(IV)‐Pd(0) bonds with potassium‐graphite (KC8). Oxidative addition of C−H or N−H bonds to the U(II) centers was observed when this transient U(II) species was treated with benzene, carbazole or 1‐adamantylamine, respectively. The U(II) centers could also react with tetracene, biphenylene or N2O, leading to the formation of arene reduced U(IV) products and uranyl(VI) species via two‐ or four‐electron processes. This study demonstrates that the intermolecular two‐electron oxidative addition reactions are viable for actinide elements. [ABSTRACT FROM AUTHOR]

Keywords: luminescence; radiation detection; scintillators; uranium As a new area in this field, uranyl-bearing scintillators show intrinsic merits for designing new materials with X-ray detection capability, that is, a large photoelectric cross-section, high X-ray attenuation efficiency, and high crystal density. Luminescence, radiation detection, scintillators, uranium. [Extracted from the article]

X‐ray detectors with high sensitivity are of great significance in both civil and military fields. Over the past decades, great efforts have been made to improve the sensitivity in conventional inorganic materials, but mainly at the cost of increasing the energy consumption with a quite high operating voltage. Developing photosensitive ferroelectrics directly as detector materials may be a conceptually new strategy in view of the strong ferroelectric spontaneous polarization (Ps) that assists photoinduced carriers separation and transport. A high‐performance X‐ray detector in 2D hybrid halide perovskite ferroelectric (C4H9NH3)2(C2H5NH3)2Pb3Br10 (BA2EA2Pb3Br10) (Ps = 5 µC cm−2) is fabricated and exhibits an ultrahigh X‐ray sensitivity up to 6.8 × 103 µC Gyair−1 cm−2 even at a relatively low operating voltage, which is over 300‐fold larger than that of state‐of‐the‐art α‐Se X‐ray detectors. Such a brilliant figure‐of‐merit is largely attributed to the superior mobility–lifetime products associated with the strong ferroelectric polarization of BA2EA2Pb3Br10. As pioneering work, these findings inform the exploration of hybrid halide perovskite ferroelectrics toward high‐performance photoelectronic devices. [ABSTRACT FROM AUTHOR]

Various types of polyoxometalates (POMs) have been synthesized since the 19th century, but their assortment has been mostly limited to Groups 5 and 6 metals. Herein, a new family of POMs composed of a carbon group element as the addenda atoms with two distinct phases, LnPbOClO4‐1 (Ln = Sm to Ho, Y) and LnPbOClO4‐2 (Ln = Er and Tm) is reported. Both structures are built from [Ln6O8] rare‐earth metal hexamers being incorporated in [Pb18O32]/[Pb12O24] polyplumbites, and unbound perchlorates as charge‐balancing anions. Impressively, YPbOClO4‐1 and ErPbOClO4‐2 exhibit exceptional uptake capacities (434.7 and 427.7 mg g−1) toward ReO4−, a chemical surrogate for the key radioactive fission product in the nuclear fuel cycle 99TcO4−, which are the highest values among all inorganic anion‐exchange materials reported until now. The sorption mechanism is clearly elucidated and visualized by single‐crystal‐to‐single‐crystal structural transformation from ErPbOClO4‐2 to a perrhenate‐containing complex ErPbOReO4, revealing a unique ReO4− uptake selectivity driven by specific interaction within Pb···O‐ReO3− bonds. [ABSTRACT FROM AUTHOR]