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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.

Radon (Rn), a ubiquitous radioactive noble gas, is the main source of natural radiation to human and one of the major culprits for lung cancer. Reducing ambient Rn concentration by porous materials is considered as the most feasible and energy-saving option to lower this risk, but the in-depth Rn removal under ambient conditions remains an unresolved challenge, mainly due to the weak van der Waals (vdW) interaction between inert Rn and adsorbents and the extremely low partial pressure (1.8 × 10

Zeolites are a well-known family of microporous aluminosilicate crystals with a wide range of industrial applications. Their industrial synthetic method under hydrothermal condition requires elevated temperature for activation of polymerization reaction and a long crystallization time, and is therefore quite energy-consuming. Herein, for the first time, we utilize high-energy ionizing irradiation (1.5 MeV electron beam) generated by an industrial electron beam 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 accumulative 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.

As a rising star among porous solid materials, covalent organic frameworks(COFs) with excellent properties including but not limit to facilely controllable structure, high porosity, and multi-chemical functionality represent significant potential for efficient 127Xe/85Kr capture and separation. In this study, through tuning the length of the organic ligands, two-dimensional(2D) COF materials with identical connection group but different pore properties, denoted as ATFG-COF and TpPa-COF with AA-stacking model and TpBD-COF with AB-stacking model were synthesized and tested for Kr and Xe adsorption for the first time. Adsorption measurements indicate that the narrower pore apertures and higher porosity are conducive for COF materials to capture Xe and Kr. Furthermore, the Henry’s constant, isosteric heat of adsorption(Qst), and ideal adsorbed solution theory(IAST) selectivity of ATFG-COF, the pore size of which is closest to the kinetic diameter of the Xe atom(0.41 nm) among 2D COF materials, were carried out based on the single component sorption isotherms. The results illustrate that the high isosteric heat values of Xe/Kr adsorption on ATFG-COF are 25 and 16 kJ/mol at room temperature, respectively. Henry’s law predicts that the selectivity factor of Xe to Kr is 6.07, consistent with the adsorption selectivity(ca. 6) calculated based on the IAST.

Summary The capture of radioiodine species during nuclear fuel reprocessing and nuclear accidents is crucial for nuclear safety, environmental protection, and public health. Previously reported emerging materials for iodine uptake cannot outperform commercial zeolites and active carbon under the practical dynamic scenario. Herein, we present a new design philosophy aiming at significantly enhanced specific host-guest interactions and obtain a nitrogen-rich covalent organic framework material by introducing a bipyridine group into the building block for the simultaneous capture of both iodine gas through enhanced electron-pair effect and organic iodide via the methylation reaction. These efforts give rise to not only an ultrahigh uptake capacity of 6.0 g g−1 for iodine gas and a record-high value of 1.45 g g−1 for methyl iodide under static sorption conditions but also, more importantly, a record-high iodine loading capability under dynamic conditions demonstrated from the breakthrough experiments.

Conventional aromatic compounds tend to exhibit the formation of sandwich-shaped excimers and exciplexes between their excited and ground states at high concentrations or in their aggregated states, causing their fluorescence to weaken or disappear due to the aggregation-caused quenching (ACQ) effect. This limits their applications in concentrated solutions or solid materials. Herein, for the first time, ACQ-based pyrene (Py) units are covalently connected to the surface of polyethylene/polypropylene nonwoven fabric (PE/PP NWF) via electron beam preradiation-induced graft polymerization followed by chemical modification. The matrix can be considered a solid solvent and Py units as a solid solute, such that the amount of Py units can be controlled by varying the reaction time. The obtained fluorescent fabric not only exhibits remarkable fluorescence properties with high fluorescence intensity, high quantum yield (>90%), and excellent fluorescence stability after laundering or in harsh chemical environments, but the fluorescence color and intensity, quantum yield, and lifetime can also be regulated by employing the ACQ effect. Additionally, the as-prepared fluorescent fabric can effectively distinguish common monocyclic aromatic hydrocarbons via a simple fluorescence response test.

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+.

Efficient xenon/krypton (Xe/Kr) separation has played an important role in industry due to the wide application of high-purity Xe and with regard to the safe disposal of radioactive noble gases (

A new technique is proposed for the in situ printing of fluorescent fabrics with superior fluorescent properties that have the potential for continuous roll-to-roll production in the industry. Nonconjugated chemical moieties were covalently connected to polyethylene/polypropylene nonwoven fabric (PE/PP NWF) to successfully prepare fluorescent PE/PP NWF, which emits a bright blue light and has a high quantum yield (∼83.35%) that can be attributed to a unique aggregation-induced emission effect. The fluorescent PE/PP NWF exhibits excellent fluorescent stability under high shear forces during accelerated laundering and in harsh chemical environments. The fluorescent PE/PP NWF can also be tailored into diverse shapes and printed in situ with high resolution. The versatility of the method was also demonstrated by fabricating fluorescent materials with different polymer matrices such as Nylon 66 fiber and PE terephthalate membrane.

Crystalline porous materials such as covalent organic frameworks (COFs) are advanced materials to tackle challenges of catalysis and separation in industrial processes. Their synthetic routes often require elevated temperatures, closed systems with high pressure, and long reaction times, hampering their industrial applications. Here we use a traditionally unperceived strategy to assemble highly crystalline COFs by electron beam irradiation with controlled received dosage, contrasting sharply with the previous observation that radiation damages the crystallinity of solids. Such synthesis by electron beam irradiation can be achieved under ambient conditions within minutes, and the process is amendable for large-scale production. The intense and targeted energy input to the reactants leads to new reaction pathways that favor COF formation in nearly quantitative yield. This strategy is applicable not only to known COFs but also to new series of flexible COFs that are difficult to obtain using traditional methods.

Crystalline solids of zeolitic imidazolate framework (ZIF)-69 with a suitable pore window size matching with atomic diameter of xenon is utilized for this task, showing notable performance for Xe/Kr capture and separation as well as decent hydrolytic and irradiation stabilities. The results illustrate that the saturated uptake amount of Xe by ZIF-69 is 2.46 mmol/g at 298 K, while Kr uptake is only 0.55 mmol/g. Importantly, the separation ratio of Xe/Kr is 8.35, one of the highest values among all solid sorbent material reported up to now. These findings suggest that ZIF-69 is a potential candidate for the application of xenon capture and purification form a gas mixture containing Kr.

A uranyl–europium heterobimetallic compound, (TEA)3[(UO2)6Eu(H2O)4(PPA)6] (H3PPA = phosphonoacetic acid, TEA = tetraethylammonium cation), was synthesized under mild hydrothermal conditions. The em...

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.

A new technique is proposed for the

A uranyl-europium heterobimetallic compound, (TEA)

Polymers with aggregation-induced emission (AIE) characteristics have attracted much attention because of their potential applications in luminescent self-assembling, anti-counterfeiting, decoration, and photoelectric devices. To date, most technologies to prepare fluorescent polymers lack versatility; moreover, the resultant material exhibits intrinsic defects of poor fluorescence intensity and durability. Herein, we covalently anchored units of tetraphenylethylene (TPE), an archetypal AIE luminogen, on the surface of conventional polymer fibers such as polyethylene/polypropylene nonwoven fabric (PE/PP NWF) via radiation-induced graft polymerization (RIGP) and subsequent chemical modification for the first time. The physicochemical properties of the original and modified fabrics were characterized in detail by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), wide-angle X-ray diffraction (WAXD), and thermogravimetric analysis (TGA). The results indicated that the TPE units were covalently and uniformly anchored on the surface of PE/PP NWF with a disordered architecture and that the as-prepared fluorescent fabric had a high thermal stability. Additionally, the fluorescent properties of the as-prepared fluorescent fabric were measured. It emitted a strong green emission and showed superior fluorescence durability after 20 cycles of accelerated laundering or in 12 M concentrated HCl and NaOH solutions.

It is still a challenge that directly reducing the uranium concentration of wastewater or radioactive wastes by adsorption to or below the criterion (30 ppb), especially from the system of low uranium concentration due to weak affinity and bad collection. Herein we have successfully introduced hydroxypyridone (HOPO) groups onto polyethylene nonwoven fabric (PENWF) surface denoted as PENWF-HOPO by radiation graft technology and follow-up two-step chemical reactions to deeply remove uranium from low-concentration (500 ppb) aqueous solutions. The chemical structures, surface morphologies, and thermal stabilities of the original and modified PENWF were characterized in detail by FT-IR, XPS, SEM, and TGA, with the results indicating successful preparation and good thermal stability of the adsorption material used under ambient conditions. Batch adsorption results show that the adsorbent removes the uranium almost completely within 12 h in a wide pH (3–10) range, and the adsorption obeys the Langmuir isotherm. Desorption and regeneration confirms its excellent regeneration and reusability (5 cycles). Importantly, this adsorbent could efficiently remove uranium (more than 97% removal ratio) from diluted aqueous solution, in which contains a serial of competing metal ions (La3+, Cr3+, Ba2+, Mn2+, Pb2+, Ni2+, Co2+, Cu2+, Zn2+, Sr2+, Cs+) or high NaF, Na2SO4, and NaH2PO4 concentrations (40 g/L).

A new macroporous ZnO/MoO 3 /SiO 2 hybrid was synthesized by a method involving sol–gel technology and biomimetic synthesis. It was characterized by Elemental analysis, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectrum (XPS) and scanning electron microscopy (SEM). Chemical degradation of 0.3 g/L Safranin T (ST) by air oxidation over macroporous ZnO/MoO 3 /SiO 2 hybrid was studied. It was found that the decolorization efficiency and the chemical oxygen demand (COD) removal of ST reached above 95.3% and 93.2%, respectively, within 25 min at room temperature and atmospheric pressure. And the organic pollutant was mineralized to simple inorganic species such as HCO 3 − , Cl − and NO 3 − , while the total organic carbon (TOC) decreased 95.4%. The structure and morphology of the catalyst were still stable after six cycling runs and the leaching test showed negligible leaching effect.

A series of cesium substituted molybovanadophosphric acids, CsxH5−xPMo10V2O40 (x = 0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5 and 5.0), were synthesized by controlling the ratio of Cs+ to PMo10V2O405−. These complexes were characterized by ICP-AES, FT-IR, XRD, nitrogen physisorption, SEM and Ho measurement. The surface area and acid strength could be adjusted by changing the molar ratio of Cs to H. The highest surface areas were obtained when x = 5 and the highest acidity when x = 0. The catalytic activity of these compounds was evaluated for the oxidation of starch by H2O2, showing that the Bronsted acidity and surface area might influence the oxidation activity. Among all the prepared catalysts, Cs3H2PMo10V2O40 exhibited the best catalytic performance with a carboxylic content of 0.59 mol per 100 g, which could be attributed to the synergy of its Bronsted acidity and surface area. This solid catalyst could be reused at least 6 times without significant loss of performance.

A series of heteropolyacid (HPA) ionic liquids [C4H6N2(CH2)3SO3H]3−nHnPW12O40 ([MIMPSH]nH3−nPW12O40, n = 1, 2 3, abbreviated as [MIMPSH]nH3−nPW) was used to catalyze one-pot depolymerization of cellulose into glucose. Their performances were much better than those of the previously reported HPAs, such as H3PW12O40, Cs2.5H0.5PW12O40. Besides cellulose, the HPA ionic liquids were able to catalyze the conversion of sucrose and starch into glucose. In addition, one-pot synthesis of levulinic acid (LA) directly from cellulose was realized using these HPA ionic liquid catalysts in a water–methyl isobutyl ketone (MIBK) biphasic system. The separation of the products and catalysts was easy, and the retrieved [MIMPSH]nH3−nPW could be repeatedly used without appreciable loss of performance.