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The development of new anode materials for LIBs with high specific energy density and long cycle performance has become urgent due to the increasing demand for further applications. Polyoxometalates (POMs), as a candidate for this filed, can afford multi-electron redox reactions while maintaining structural integrity, which is beneficial for a large amount of electrons and charge transfer during charging/discharging. Here, for the first time, we report a POM-based metal–organic framework with a woven fabric structure, showing a discharge specific capacity of 788 mA h g−1 at a current density of 200 mA g−1. After carbon nanotube coating post-synthesis, the discharge specific capacity increased to 1000 mA h g−1 and exhibited evident cycling stability. Combining POMOF with CNT, as synergistic strategy, is a feasible way to exploit new anode materials with higher performance for LIBs. [ABSTRACT FROM AUTHOR]

Regorafenib (REG) is an oral multikinase inhibitor used for the treatment of gastrointestinal stromal tumors, metastatic colorectal cancer and advanced hepatocellular carcinoma. REG exists in various crystal forms and its monohydrate form (REG·H2O) is selected as the commercial form. However, the clinical efficacy of REG is severely limited by low oral bioavailability due to its poor aqueous solubility. With the intention to expand the solid forms and to improve the aqueous solubility at the same time, three cocrystals of REG with malonic acid (REG–MA), glutaric acid (REG–GA) and pimelic acid (REG–PA) were successfully synthesized by liquid-assisted grinding and/or the slurry methods. The obtained cocrystals were fully characterized by X-ray diffraction analysis, thermal analysis, and Fourier transform infrared and proton nuclear magnetic resonance spectroscopy, and were then subjected to powder dissolution, dynamic vapor sorption, stability and tabletability investigations. As compared to REG·H2O, REG–MA exhibits comparable dissolution behavior, while REG–GA and REG–PA demonstrate significantly enhanced apparent solubility and dissolution rates without compromising the hygroscopicity and physicochemical stability of the drug. In addition, the formation of the cocrystals also improves the tabletability of the powdered samples. These results suggest that REG–GA and REG–PA have great potential to be developed as new, more efficient formulations of REG. [ABSTRACT FROM AUTHOR]

In the complex synthesis process, the design of new type structures of lanthanide clusters with high nuclearity provides an opportunity to understand the nature of magnetic dynamics. Here, the homometallic dodecanuclear complexes with the formula [Ln12(H2L1)4(μ3-O)4(μ3-OH)4(CH3COO)15]·(CH3COO)·(CH3OH)6 (Ln = Dy (1) and Gd (2)) were synthesized using 2,6-bis(2-((E)-2-hydroxybenzylidene)hydrazine-1-carbonyl)pyridine 1-oxide (H4L1) ligand and Ln(CH3COO)3·6H2O in CH3OH. The structural analysis showed that those complexes had novel cores in Ln-clusters. In the main core of [Ln12(μ3-OH)4(μ3-O)4(μ2-O)14], the center was a cubic [Ln4(μ3-O)4]4− structure. In the [Ln4(μ3-O)4]4− structure, each Ln(III) ion and the other two Ln(III) ions formed a triangular [Ln3(μ3-O)(μ2-O)3] structure under the connection of oxygen bridges. Magnetic property measurements revealed that complex 1 showed weak single-molecule magnetic behavior, while complex 2 showed large magnetocaloric effects (MCEs). [ABSTRACT FROM AUTHOR]

In recent years, low-dimensional organic–inorganic hybrid lead halide perovskites have been explored as photoluminescent (PL) materials with high photoluminescence quantum efficiencies and tunable band structures arising from the structural regulating functions of organic cations. Herein, by using a simple solution reaction, we prepared one new type of one-dimensional (1D) hybrid lead halide, namely [DMEDA]PbCl4 (DMEDA = N,N′-dimethylethylenediamine). The compound contains 1D edge sharing octahedral lead chloride [PbCl4]2− anionic chains, which are surrounded and separated by organic cations of [DMEDA]2+. This 1D structure enables the formation of self-trapped excited states that give bright yellow emission with a photoluminescence quantum efficiency (PLQE) of approximately 4.81%. A white light emitting device can also be easily fabricated by coating a sample of [DMEDA]PbCl4 on a blue light chip. Its PL stability and nature are also investigated by using various experiments. This work provides a new type of structural model to probe the PL properties and understand the structure–property relationship of low-dimensional lead halide perovskites. [ABSTRACT FROM AUTHOR]

We utilise the dual synthesis strategy in terms of bimetallic inorganic building blocks and sulfur containing organic ligand. A novel sulfur-containing bimetallic metal organic framework (Fe2Co-TPDC) with two types of 4-fold meso-helical structures has been successfully synthesized. Benefitting from the uniform distribution of active sulfur sites and the structural stability of the mixed-metallic method, Fe2Co-TPDC can efficiently prevent a shuttle behavior of sulfur and endow a commendable specific capacity. As far as we know, this is the first time that a sulfur-containing bimetallic crystalline MOF with helical structure and prominent specific capacity and remarkable cycling stability has served as an electrode material for LIBs. [ABSTRACT FROM AUTHOR]

Unprecedented polyoxometalate based metal–carbene frameworks (POM-based MCFs) [Cu10(H3trz)4(Htrz)4](HPW12O40) (1) and [Cu10(H3trz)4(Htrz)4](H2SiW12O40) (2) have been fabricated via a hydrothermal reaction between 1,2,4-triazole and Cu(CH3COO)2 with the saturated Keggin polyoxoanion [PW12O40]3−/[SiW12O40]4− as a template for the first time. Single crystal X-ray diffraction analysis reveals the successful encapsulation of Keggin POMs into the three-dimensional POM-based MCFs with lvt-a topology based on their effective coordination with Cu ions. Interestingly, these novel 3D POM-based MCFs exhibit good electrochemical performance in lithium-ion batteries (LIBs) as anode materials, with first discharge capacities of ca. 1620 and 1245 mA h g−1 for 1 and 2, respectively, at a current density of 100 mA g−1, and stabilized discharge capacities of ca. 570 mA h g−1 for 1 and 426 mA h g−1 for 2 after 100 cycles. This, in combination with their high thermal stability, suggests their good LIB application potential. [ABSTRACT FROM AUTHOR]

The first mixed-valence nickel-supported polyoxometalate-based metal–organic framework, (H2mim)[NiIII(Hmim)4][SiW11NiIIO37(OH)2(Hmim)]·3H2O (1) (Hmim = 2-methylimidazole), has been synthesized using a steam-assisted conversion method, and is constructed from noncovalent interactions (hydrogen bonds and π…π stacking interactions). 1 has a repeating honeycomb-shaped internal structure with one-dimensional channels along the direction of the c axis, where the diameter of the aperture is as large as 18.83 Å. Furthermore, the stability and the optical band gaps are investigated. [ABSTRACT FROM AUTHOR]

The crystal structure of Cd-MOF-74 was obtained for the first time that possesses high sensitivity for the detection of copper ions from water and simulated biological fluids based on changes in luminescent intensity. Furthermore, Cd-MOF-74 could selectively remove Cu2+ from simulated biological fluids that contain Mg2+, Co2+, Zn2+, Fe2+, Ni2+, Na+, and K+. The adsorption capacity of this adsorbent for copper ions reached 189.5 mg g−1 and it quickly adsorbed copper ions within 10 minutes under 10 ppm Cu2+ in the simulated biological system. XPS, PXRD, and gas adsorption measurements revealed that this high sensitivity and selectivity of Cd-MOF-74 resulted from the partial substitution of Cd2+ by Cu2+ in the framework. Although many MOF materials have been employed for sensor or selective adsorption of Cu2+, Cd-MOF-74 is the first example of MOFs showing both capabilities in simulated biological fluids, which represents a pioneering work that extends the applications of MOF materials in the biological field. [ABSTRACT FROM AUTHOR]

The crystal structure of Cd-MOF-74 was obtained for the first time that possesses high sensitivity for the detection of copper ions from water and simulated biological fluids based on changes in luminescent intensity. Furthermore, Cd-MOF-74 could selectively remove Cu 2+ from simulated biological fluids that contain Mg 2+ , Co 2+ , Zn 2+ , Fe 2+ , Ni 2+ , Na + , and K + . The adsorption capacity of this adsorbent for copper ions reached 189.5 mg g -1 and it quickly adsorbed copper ions within 10 minutes under 10 ppm Cu 2+ in the simulated biological system. XPS, PXRD, and gas adsorption measurements revealed that this high sensitivity and selectivity of Cd-MOF-74 resulted from the partial substitution of Cd 2+ by Cu 2+ in the framework. Although many MOF materials have been employed for sensor or selective adsorption of Cu 2+ , Cd-MOF-74 is the first example of MOFs showing both capabilities in simulated biological fluids, which represents a pioneering work that extends the applications of MOF materials in the biological field.

A new hybrid compound, Na[Ag6(pyttz)2(H2O)][PMo12O40] (pyttz = 3-(pyrid-3-yl)-5-(1H-1,2,4-triazol-3-yl)-1,2,4-triazolyl), has been hydrothermally synthesized and structurally characterized by routine techniques. X-ray diffraction analysis reveals that the title compound is constructed by the 2D Ag-pyttz coordination polymer and 3D Ag-POM architecture with helix. A fascinating structural feature is the assembling fashion of the right- and left-helical chain, namely, the helical chains with different orientations are intertwined with each other forming intertwined double helical layers along the c-axis, and the identical left- or right-handed helical chains are fused together in a hand-by-hand mode generating another homological helical layer along the a-axis. As a result, these helical layers intersect each other obtaining an unprecedented 3D POM-Ag inorganic architecture. Note that the 3D framework with a helix constructed by POMs and metal ions has never been observed up to date. Additionally, its photocatalytic degradation of RhB was also investigated.

To investigate the influence of a secondary spacer on the resulting structures of POMOFs containing pytz, five new compounds with different dimensionalities, [Cu(5)(2-pytz)(6)(H(2)O)(4)][SiMo(12)O(40)]·3H(2)O (1), [Cu(3)(2-pytz)(4)bipy][H(2)SiMo(12)O(40)]·bipy (2), [Cu(3)(2-pytz)(2)(bipy)(4)(H(2)O)(6)][H(4)SiW(12)O(40)](2)·6H(2)O (3), [Cu(2)(2-pytz)(phen)(OH)](2)[SiW(12)O(40)]·H(2)O (4), [Cu(3)(4-pytz)(4)(H(2)O)(4)][H(2)SiW(12)O(40)]·2H(2)O (5), were synthesized. When only 2-pytz was employed, compound 1 with a 3D framework was obtained, whereas when the secondary spacers (4,4'-bipy, phen and 4-pytz) were introduced into the reaction system of 1, compounds 2-5 were obtained and exhibit a broad range of structures, including 0D, 1D, 2D and 3D frameworks. It can be observed from the architectures of compounds 1-5 that the secondary spacers have a great effect on the structures of the MOFs, which results in the formation of various dimensional POMOF compounds. Additionally, photocatalytic experiments of 1-5 for the photocatalytic degradation of RhB under UV irradiation were also investigated.