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Carbon emission reduction is an important measure to mitigate the greenhouse effect, which has become a hotspot in global climate change research. To contribute to this, here, we fabricated two Co-based metal-organic frameworks (Co-MOFs), namely, {[Co3(NTB)2(bib)]·(DMA)2·(H2O)4}n (DZU-211) and {[Co3(NTB)2(bmip)]·(DMA)2}n (DZU-212) (H3NTB = 4,4',4â³-nitrilotribenzoic acid, bib = 1,4-bis(imidazol-1-yl)-butane, bmip = 1,3-bis(2-methyl-1H-imidazol-1-yl)propane) to realize efficient CO2/N2 separation by dividing coordination spaces into suitable pores with narrow windows. DZU-211 reveals a 3D open porous framework, while DZU-212 exhibits a 3D double-fold interpenetrated structure. The two MOFs both possess large coordination spaces and small open pore sizes, via the bib ligand insertion and framework interpenetration, respectively. Comparatively, DZU-211 reveals superior selective CO2 uptake properties due to its more suitable pore characteristics. Gas sorption experiments show that DZU-211 has a CO2 uptake of 52.6 cm3 g-1 with a high simulated CO2/N2 selectivity of 101.7 (298 K, 1 atm) and a moderate initial adsorption heat of 38.1 kJ mol-1. Moreover, dynamic breakthrough experiments confirm the potential application of DZU-211 as a CO2 separation material from postcombustion flue gases.
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To conquer the bottleneck of sluggish kinetics in cathodic oxygen reduction reaction (ORR) of metal-air batteries, catalysts with dual-active centers have stood out. Here, a "pre-division metal clusters" strategy is firstly conceived to fabricate a N,S-dual doped honeycomb-like carbon matrix inlaid with CoN4 sites and wrapped Co2 P nanoclusters as dual-active centers (Co2 P/CoN4 @NSC-500). A crystalline {CoII 2 } coordination cluster divided by periphery second organic layers is well-designed to realize delocalized dispersion before calcination. The optimal Co2 P/CoN4 @NSC-500 executes excellent 4e- ORR activity surpassing the benchmark Pt/C. Theoretical calculation results reveal that the CoN4 sites and Co2 P nanoclusters can synergistically quicken the formation of *OOH on Co sites. The rechargeable Zn-air battery (ZAB) assembled by Co2 P/CoN4 @NSC-500 delivers ultralong cycling stability over 1742â hours (3484â cycles) under 5â mA cm-2 and can light up a 2.4â V LED bulb for ≈264â hours, evidencing the promising practical application potentials in portable devices.
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Layering AgNO3 in alcohol onto octavinylsilsesquioxane (OVS) in CHCl3 results in a one-dimensional coordination polymer, {Ag4(NO3)4(OVS)·solvents}n (SD/Ag4a-d), consisting of unprecedented flat weakly bonded Ag4(NO3)4 alternating with the firmly covalent OVS through AgI-πCâC bonds. The preferential assembling medium for SD/Ag4a is proven to be alcohols, where a 4:1 silver-OVS adduct is detected by electrospray ionization mass spectrometry. The present outcomes may assist our knowledge of particular interactions for supramolecular architectures of a polynuclear silver system built from OVS containing eight pendent olefin tails.
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Luminescent metal-organic frameworks (LMOFs) as sensors showing highly efficient detection toward toxic heavy-metal ions are in high demand for human health and environmental protection. A novel nanocage-based N-rich LMOF (LCU-103) has been constructed and characterized. It is a 2-fold interpenetrating structure built from N-rich {Zn6(dttz)4} nanocages extended by N-donor ligand Hdpa [H3dttz = 4,5-di(1H-tetrazol-5-yl)-2H-1,2,3-triazole; Hdpa = 4,4'-dipyridylamine]. Notably, LCU-103 contains abundant N functional sites anchoring on both the windows of nanocages and the inner channels of the framework that can interact with metal ions and then recognize them. As a result, it can serve as a luminescent sensing material for detecting trace amounts of Fe3+ and Cu2+ ions with low limits of detection (LODs) of 1.45 and 1.66 µM, respectively, through a luminescent quenching mechanism. Meanwhile, LCU-103 as a LMOF sensor exhibits several advantages such as high sensitivity, appropriate selectivity (for Fe3+ in H2O), recycling stability, and fast response times in N,N-dimethylformamide. Moreover, LCU-103 also displays good luminescent quenching activity toward Fe3+ in H2O and a simulated 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid biological system with low LODs of 1.51 and 1.52 µM, respectively. LCU-103 test papers were further prepared to offer easy and real-time detection of Fe3+ and Cu2+ ions. Importantly, when density functional theory calculations and multiple experimental evidence, including X-ray photoelectron spectroscopy, UV-vis absorption, luminescence decay lifetimes, and quantum efficiencies, are combined, a preferred N-donor site and possible weak interaction sensing mechanism is also proposed to elucidate the quenching effect.
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Six novel copper(I) cluster-based coordination polymers (CPs) [Cu9(pzt)7Cl2]n (1), [Cu2(pzt)Cl]n (2), [Cu4(pzt)3Br]n (3), [Cu(pzt)]n (4), [Cu4(pzt)3I]n (5), and [Cu7(pzt)6I]n (6) were solvothermally synthesized using Hpzt (Hpzt = pyrazine-2-thiol) ligand and well-characterized by elemental analysis, infrared (IR) spectroscopy, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction (SCXRD). Six CPs exhibit either 2D (4 and 6) or 3D (1-3, and 5) network based on diverse multinuclear {CuxSy} clusters. The structural evolutions of 1-6 are greatly influenced by types of metal halides and the ligand-to-metal molar ratio used in the reaction. Among them, compound 1 displays interesting temperature-dependent photoluminescence arising from triplet cluster-centered (3CC) excited state from the cluster metal core. Compounds 1-6 also exhibit photocurrent responses upon visible-light illumination (λ = 420 nm) in the order 6 > 5 > 3 > 1 > 4 > 2. This work not only shows the structural diversity of {CuxSy} clusters-based CPs but also provides an interesting insight into structural modulation using crystal engineering concept.
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Two novel space craft-like octanuclear Co(II)-silsesquioxane nanocages, {Co8[(MeSiO2)4]2(dmpz)8} (SD/Co8a) and {Co8[(PhSiO2)4]2(dmpz)8} (SD/Co8b) (SD = SunDi; Hdmpz = 3,5-dimethylpyrazole), have been constructed from two similar multidentate silsesquioxane ligands assisted with a pyrazole ligand. The Co8 skeleton consists of eight tetrahedral Co(II) ions arranged in a ring and is further capped by two (MeSiO2)4 ligands up and down. The auxiliary dmpz- ligands seal the ring finally. Electrospray ionization mass spectrometry revealed SD/Co8a and SD/Co8b are highly stable in CH2Cl2. Magnetic analysis implies that SD/Co8a announces antiferromagnetic interactions between Co(II) ions. Moreover, both of them display good homogeneous catalytic activity for hydroboration of ketones in the presence of pinacolborane under mild conditions.
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Two novel POM-based inorganic-organic hybrids, [Cu6II(2,2'-bipy)6(Mo6O22)(SiW12O40)]n (1), and {[Cu6II(ppz)6(H2O)5(MoO4)(SiW12O40)]·4H2O}n (2) (2,2'-bipy = 2,2'-bipyridine, Hppz = 3-(pyrid-2-yl)pyrazole), have been constructed from heteropolytungstates and molybdates. Two compounds have been identified by single crystal X-ray diffraction, elemental analysis, and FT-IR. Compound 1 shows a 1D (one-dimensional) chain structure constructed from classical Keggin heteropolytungstate [SiW12O40]4- clusters and [Cu6(2,2'-bipy)6] modified isopolymolybdates [Mo6O22]8-. Compound 2 also represents a 1D chain-like motif built from classical Keggin heteropolytungstate [SiW12O40]4- clusters and [Cu8(ppz)6(H2O)5] modified molybdates MoO42-. Compound 1 represents the first example of POM-based inorganic-organic hybrid with mixed heteropolytungstates and isopolymolybdates. ESI-MS (electrospray ionization mass spectrometry) technique was employed to reveal the species and their evolutions in the hydrothermal reaction, whereby trivacant [SiW9] building block gradually transforms to classical Keggin [SiW12] during assembly process. Furthermore, the electrocatalytic and magnetic properties were discussed in details.
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Carbonaceous aerosol, as an important component of atmospheric aerosol, has a significant impact on atmospheric environmental quality, human health, and global climate change. To investigate the characteristics and sources of carbonaceous aerosol in atmospheric fine particulate matter (PM2.5) in Huaxi District of Guiyang, an in-situ observational study was conducted during different seasons in 2020, and the carbonaceous components of PM2.5 were measured using a thermal-optical carbon analyzer (DRI Model 2015). The results of the study showed that the average concentrations of PM2.5, total carbonaceous aerosol (TCA), organic carbon (OC), secondary organic carbon (SOC), and elemental carbon (EC) concentrations during the observation period were (39.7±22.3), (14.1±7.2), (7.6±3.9), (4.4±2.6), and (2.0±1.0) µg·m-3, respectively, and the mean value of OC/EC was (3.9±0.8). ρ(PM2.5), ρ(TCA), ρ(OC), ρ(SOC), and ρ(EC) showed a seasonal variation pattern with the highest in winter [(52.6±28.6), (17.0±9.6), (9.1±5.2), (6.1±3.9), and (2.4±1.2) µg·m-3, respectively] and the lowest in summer [(25.1±7.1), (11.6±3.6), (6.3±1.9), (3.7±1.2), and (1.6±0.6) µg·m-3, respectively]. The seasonal variation in OC/EC showed summer (4.2±0.8) > winter (3.8±0.9) > autumn (3.8±0.5) > spring (3.7±0.9), indicating the presence of SOC generation in all seasons in Huaxi District. SOC showed a significant correlation with OC (R2 =0.9), and the SOC concentration tended to increase with the increase in atmospheric oxidation. OC showed a good correlation with EC in all seasons, with the highest in autumn (R2 =0.9) and lower correlations in the other three seasons (R2 ranged from 0.74 to 0.75), indicating a common source. According to OC/EC ratio range, it was preliminarily determined that carbonaceous aerosol came from vehicle exhaust emissions, coal burning emissions, and biomass combustion emissions. In order to further quantify the contribution of major emission sources to carbonaceous aerosol, the results of this study using PMF to analyze the sources of carbonaceous aerosol showed that the main sources of carbonaceous aerosol in Huaxi District of Guiyang were coal combustion sources (29.3%), motor vehicle emission sources (21.5%), and biomass combustion sources (49.2%).
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The cathodic product Li2CO3, due to its high decomposition potential, has hindered the practical application of rechargeable Li-CO2/O2 batteries. To overcome this bottleneck, a Pt/FeNC cathodic catalyst is fabricated by dispersing Pt nanoparticles (NPs) with a uniform size of 2.4 nm and 8.3 wt % loading amount into a porous microcube FeNC support for high-performance rechargeable Li-CO2/O2 batteries. The FeNC matrix is composed of numerous two-dimensional (2D) carbon nanosheets, which is derived from an Fe-doping zinc metal-organic framework (Zn-MOF). Importantly, using Pt/FeNC as the cathodic catalyst, the Li-CO2/O2 (VCO2/VO2 = 4:1) battery displays the lowest overpotential of 0.54 V and a long-term stability of 142 cycles, which is superior to batteries with FeNC (1.67 V, 47 cycles) and NC (1.87 V, 23 cycles) catalysts. The FeNC matrix and Pt NPs can exert a synergetic effect to decrease the decomposition potential of Li2CO3 and thus enhance the battery performance. In situ Fourier transform infrared (FTIR) spectroscopy further confirms that Li2CO3 can be completely decomposed under a low potential of 3.3 V using the Pt/FeNC catalyst. Impressively, Li2CO3 exhibits a film structure on the surface of the Pt/FeNC catalysts by scanning electron microscopy (SEM), and its size can be limited by the confined space between the carbon sheets in Pt/FeNC, which enlarges the better contacting interface. In addition, density functional theory (DFT) calculations reveal that the Pt and FeNC catalysts show a higher adsorption energy for Li2CO3 and Li2CO4 intermediates compared to the NC catalyst, and the possible discharge pathways are deeply investigated. The synergetic effect between the FeNC support and Pt active sites makes the Li-CO2/O2 battery achieve optimal performance.
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BACKGROUND: This study aims to explore whether Fufang Shatai Heji (STHJ), as a mixture collected by a decoction of a variety of Chinese herbal medicines for immune system diseases, can improve the cartilage destruction of rheumatoid arthritis (RA). METHODS: The therapeutic effects of STHJ were studied using collagen induced arthritis (CIA) mice. The improvement effect of STHJ on synovitis and cartilage damage caused by arthritis was studied by joint pathological analysis. The inhibitory effect of STHJ on related degradation enzymes in cartilage was studied by immunohistochemistry and real-time polymerase chain reaction (PCR). The specific targets of STHJ were predicted by molecular docking. RESULTS: After successfully inducing CIA, the paws of the mice showed significant swelling, and athological analysis of the ankle and knee joints also showed significant cartilage destruction and synovial hyperplasia. However, synovial hyperplasia and cartilage destruction were markedly alleviated after administration of STHJ. And after STHJ treatment, the expression of ADAMTS-4, ADAMTS-5, MMP-9 and MMP-13, in the cartilage layer of CIA mice was significantly inhibited. Through molecular docking assays, we proved that acteoside in STHJ could directly bind to the Glu111, Phe110 residues in MMP-9 and glycyrrhizic acid in STHJ bind to the Glu382, Asn433 residues in MMP-13. CONCLUSIONS: Our results suggested that STHJ may alleviate synovial hyperplasia and cartilage destruction in CIA mice and protect cartilage by inhibiting the expression of MMP-9 and other enzymes.
Assuntos
Artrite Experimental , Medicamentos de Ervas Chinesas , Animais , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Cartilagem/metabolismo , Cartilagem/patologia , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Metaloproteinases da Matriz/metabolismo , Metaloproteinases da Matriz/farmacologia , Metaloproteinases da Matriz/uso terapêutico , Camundongos , Simulação de Acoplamento MolecularRESUMO
High-performance lithium ion batteries (LIBs) juggling high reversible capacity, excellent rate capability and ultralong cycle stability are urgently needed for all electronic devices. Here we report employing a vesicle-like porous N-doped carbon material (abbr. N/C-900) as a highly active anode for LIBs to balance high capacity, high rate and long life. The N/C-900 material was fabricated by pyrolysis of a designed crystal MOF LCU-104, which exhibits a graceful two-fold interpenetrating structural feature of N-rich nanocages {Zn6(dttz)4} linked through an N-donor ligand bpp (H3dttz = 4,5-di(1H-tetrazol-5-yl)-2H-1,2,3-triazole, bpp = 1,3-bis(4-pyridyl)propane). The features of LCU-104 combine high N content (35.1%), interpenetration, and explosive characteristics, which endow the derived N/C material with optimized N-doping for tuning its chemical and electronic structure, a suitably thicker wall to enhance its stability, and a vesicle-like structure to improve its porosity. As an anode material for LIBs, N/C-900 delivers a highly reversible capacity of ca. 734 mA h g-1 at a large current density of 1 A g-1 until the 2000th cycle, revealing its ultralong cycle stability and excellent rate capability. The unique structure and preferential interaction between abundant pyridinic N active sites and Li atoms are responsible for the improved excellent lithium storage capacity and durability performances of the anode according to analysis of the results of computational modeling.
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Three Mn-MOFs {[Mn3(µ4-L)2(H2O)7]·4H2O}n (1), {[Mn3(µ5-L)2(H2O)6]·4H2O}n (2) and {[Mn3(µ7-L)2(H2O)2]}n (3) (H3L = 5-(6-carboxypyridin-3-yl)isophthalic acid) were obtained under different reaction times and temperatures. Interestingly, induced by reaction time, compound 1 can lose one water molecule and SC-SC transform into compound 2. Similarly, compound 2 can also SC-SC transform into 3. Studies on two SC-SC transformation processes were carried out and the transformation mechanisms were deduced, which were verified by TG analyses. Different numbers of water molecules in the three compounds resulted in different coordination environments of the metal cation, coordination modes of the L3- ligand, continuities of hydrogen bonds, dimensions of framework and porosities. The AC impendence spectra studies revealed that compounds 1-3 can enhance the proton conductivities of the Nafion composite membrane to about 47.77%, 36.88% and 21.28%, respectively. It is speculated that the highest proton conductivity of compound 1 may be due to its continuous hydrogen bond chain and highest water uptake, which were mainly decided by the number of water molecules.
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The exploitation of efficient hydrogen evolution reaction (HER) electrocatalysts has become increasingly urgent and imperative; however, it is also challenging for high-performance sustainable clean energy applications. Herein, novel Co9S8 nanoparticles embedded in a porous N,S-dual doped carbon composite (abbr. Co9S8@NS-C-900) were fabricated by the pyrolysis of a single crystal Co-MOF assisted with thiourea. Due to the synergistic benefit of combining Co9S8 nanoparticles with N,S-dual doped carbon, the composite showed efficient HER electrocatalytic activities and long-term durability in an alkaline solution. It shows a small overpotential of -86.4 mV at a current density of 10.0 mA cm-2, a small Tafel slope of 81.1 mV dec-1, and a large exchange current density (J 0) of 0.40 mA cm-2, which are comparable to those of Pt/C. More importantly, due to the protection of Co9S8 nanoparticles by the N,S-dual doped carbon shell, the Co9S8@NS-C-900 catalyst displays excellent long-term durability. There is almost no decay in HER activities after 1000 potential cycles or it retains 99.5% of the initial current after 48 h.
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Electrochemical water splitting is convinced as one of the most promising solutions to combat the energy crisis. The exploitation of efficient hydrogen and oxygen evolution reaction (HER/OER) bifunctional electrocatalysts is undoubtedly a vital spark yet challenging for imperative green sustainable energy. Herein, through introducing a simple pH regulated redox reaction into a tractable hydrothermal procedure, a hierarchical Fe3O4@MnOx binary metal oxide core-shell nano-polyhedron was designed by evolving MnOx wrapped Fe3O4. The MnOx effectively prevents the agglomeration and surface oxidation of Fe3O4 nano-particles and increases the electrochemically active sites. Benefiting from the generous active sites and synergistic effects of Fe3O4 and MnOx, the Fe3O4@MnOx-NF nanocomposite implements efficient HER/OER bifunctional electrocatalytic performance and overall water splitting. As a result, hierarchical Fe3O4@MnOx only requires a low HER/OER overpotential of 242/188 mV to deliver 10 mA cm-2, a small Tafel slope of 116.4/77.6 mV dec-1, combining a long-term cyclability of 5 h. Impressively, by applying Fe3O4@MnOx as an independent cathode and anode, the overall water splitting cell supplies a competitive voltage of 1.64 V to achieve 10 mA cm-2 and super long cyclability of 80 h. These results reveal that this material is a promising candidate for practical water electrolysis application.
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PURPOSE: To overcome negative adverse effects and improve therapeutic index of dexamethasone (Dex) in rheumatoid arthritis (RA), we developed a novel sustained release formulation-intra-articular injectable dexamethasone-loaded thermosensitive hydrogel (DLTH) with chitosan-glycerin-borax as carrier for the remission of inflammation and pain. The focus of this article is to explore both anti-inflammatory and pain-relieving effects of DLTH joint injection in bovine type-II collagen-induced arthritis (CIA) rats. METHODS: Wistar rats were randomized into three groups, including the normal group (n=6), the model group (n=6) and the DLTH group (n=10). Joint injection of DLTH (1mg/kg Dex per rat) was injected on day 12 in the DLTH group twice a week for three weeks. Clinical signs of body weight, paw swelling and arthritis scores, histologic analysis, hind paw mechanical withdrawal threshold (MWT), plantar pressure pain threshold (PPT) were taken into consideration. Serum contents of IL-17A, prostaglandin E2 (PGE2), prostacyclin 2 (PGI2) and prostaglandin D2 (PGD2), real-time polymerase chain reaction (PCR) analysis of inflammatory factors and pain-related mediators in synovium and dorsal root ganglia (DRG), Western blotting of NF-κB in synovium were all evaluated. RESULTS: Paw swelling, arthritis scores and joint inflammation destruction were all attenuated in the DLTH-treated group. Results showed that DLTH not only down-regulated serum IL-17A, but also mRNA levels of inflammatory factors and NGF, and key proteins contents of the NF-κB pathway in synovium. Increases of MWT and PPT in DLTH-treated rats elucidated pain-reducing effects of DLTH. Elevated serum PGD2 levels and declines of serum PGE2 and PGI2, and inflammatory and pain-related genes in DRGs in the DLTH group were also recorded. CONCLUSION: These data elucidated that DLTH joint injection impeded synovial inflammation processes through down-regulating transcription activity of NF-κB pathway, and intra-articular DLTH may aid in the regulation of RA pain through regulating inflammation and pain conduction process.
Assuntos
Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Artrite Experimental/tratamento farmacológico , Dexametasona/administração & dosagem , Dexametasona/farmacologia , Inflamação/tratamento farmacológico , Dor/tratamento farmacológico , Animais , Artrite Experimental/patologia , Artrite Experimental/psicologia , Peso Corporal/efeitos dos fármacos , Dinoprostona/metabolismo , Edema/tratamento farmacológico , Gânglios Espinais/efeitos dos fármacos , Hidrogéis , Inflamação/induzido quimicamente , Interleucina-17/metabolismo , Masculino , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Dor/induzido quimicamente , Limiar da Dor/efeitos dos fármacos , Prostaglandina D2/metabolismo , Ratos , Ratos Wistar , Membrana Sinovial/patologiaRESUMO
The construction of an efficient oxygen reduction reaction and oxygen evolution reaction (ORR/OER) bifunctional electrocatalyst is of great significance but still remains a giant challenge for high-performance metal-air batteries. In this study, uniform FeS/Fe3C nanoparticles embedded in a porous N,S-dual doped carbon honeycomb-like composite (abbr. FeS/Fe3C@NS-C-900) have been conveniently fabricated by pyrolysis of a single-crystal Fe-MOF, which has a low potential gap ΔE of ca. 0.72 V, a competitive power density of 90.9 mW/cm2, a specific capacity as high as 750 mAh/gZn, and excellent cycling stabilities over 865 h (1730 cycles) at 2 mA/cm2 when applied as a cathode material for rechargeable zinc-air batteries. In addition, the two series-linked Zn-air batteries successfully powered a 2.4 V LED light as a real power source. The efficient ORR/OER bifunctional electrocatalytic activity and long-term durability of the obtained composite might be attributed to the characteristic honeycomb-like porous structure with sufficient accessible active sites, the synergistic effect of FeS and Fe3C, and the N,S codoped porous carbon, which provides a promising application potential for portable electronic Zn-air battery related devices.
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Fufang Shatai Heji (STHJ) is a mixture of traditional Chinese medicines, such as Radix Adenophorae, Radix Pseudostellariae, and Radix Astragali. STHJ is commonly used to treat diseases caused by low immune function, for example, Sjögren's syndrome (SS). The primary objective of this study was to assess the immunopotentiating effect of STHJ using an immunosuppressive mouse model receiving cyclophosphamide (CTX). Following CTX treatment, STHJ was administered by oral gavage for 30 consecutive days. The percentage of specific lymphocyte subpopulations in the spleen was measured by flow cytometry. Levels of inflammatory factors in serum were detected by enzyme-linked immunosorbent assays (ELISAs). The administration of STHJ significantly elevated thymus and spleen indices, increased B cell and natural killer (NK) cell activities, and decreased CD8+ T, CD8+CD122+ T, NKT, and γδT cell activities in the CTX-treated mice. In addition, STHJ upregulated the expression of interleukin- (IL-) 2, IL-6, and tumor necrosis factor-α (TNF-α) and downregulated IL-10 expression in CTX-treated mice. In conclusion, STHJ effectively remitted CTX-induced immunosuppression by modulating the balance of lymphocyte subsets and cytokines. Our results suggest STHJ treatment could be used as an effective therapeutic approach to improve immune function in patients with low immunity.
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The introduction of hexavacant Dawson-type precursor K(12)[H(2)P(2)W(12)O(48)] x 24 H(2)O into a HOAc/NaOAc (OAc(-) = acetate) buffer system containing (NH(4))(2)[Ce(IV)(NO(3))(6)] and Mn(II)(OAc)(2) x 4 H(2)O led to the isolation of a new compound, Na(20)[Ce(IV)(3)Mn(IV)(2)O(6)(OAc)(6)(H(2)O)(9)](2)[Mn(III)(2)P(2)W(16)O(60)](3) x 21 H(2)O (1). Compound 1 contains unusual triple-Dawson-type polyoxoanions [Mn(III)(2)P(2)W(16)O(60)](3)(24-) and bipyramid-like 3d-4f heterometallic clusters [Ce(IV)(3)Mn(IV)(2)O(6)(OAc)(6)(H(2)O)(9)](2+), which are arranged in a 3-D supramolecular assembly with 1-D channels. The Na(+) cations and solvent water molecules reside in the channels. Crystal data for 1 are as follows: hexagonal, P6(3)/mcm (No. 193), a = 24.959(4) A, c = 26.923(5) A, gamma = 120 degrees, V = 14525(4) A(3), and Z = 2. The electrochemical and electrocatalytic properties of compound 1 have been investigated.
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Metais/química , Compostos de Tungstênio/química , Cristalografia por Raios X , Metais/síntese química , Modelos Moleculares , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Tungstênio/síntese químicaRESUMO
Simultaneously involving abundant [NH2(CH3)2]+ cations and uncoordinated carboxylate oxygen atoms as dual active sites, two microporous CoII-MOFs (LCU-105 and LCU-106, LCU = Liaocheng University) both exhibit highly selective adsorption of CO2/CH4 and CO2/N2. GCMC theoretical simulations provide good verification of the experimental results.
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Two isostructural nanocage-based porous Ni/Co(II)-MOFs have been hydrothermally synthesized, which were interestingly composed of icosahedron and tetrahedron cages with a new (3,8)-connected 3D topology. Moreover, the stable Ni-MOF exhibits good selective CO2/CH4 and CO2/N2 adsorption owing to its exposed nitrogen active sites.