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Five new inorganic–organic hybrid compounds, [Co2(HDIBA)2(DIBA)2(H2O)4]·HPW12O40·2H2O (1), [Ni2(HDIBA)2(DIBA)2(H2O)4]·HPW12O40 (2), [Ag(H2DIBA)2·PW12O40]·2H2O (3), [Ag(H2DIBA)2·PMo12O40]·2H2O (4) and [Ag(H2DIBA)2·HSiMo12O40]·2H2O (5) (HDIBA = 3,5-di(1H-imidazol-1-yl)benzoic acid), based on Keggin-type polyoxometalates (POMs) have been synthesized by a hydrothermal method. Their structures were characterized through single-crystal X-ray diffraction, elemental analysis, powder X-ray diffraction, IR spectroscopy and thermogravimetric analysis. The discrete units of 1 are further extended into a 3D supramolecular structure by π–π stacking and hydrogen bonding interactions. In compound 2, wavy ladderlike bimetallic chains are linked by hydrogen bonding interactions to form a 3D supramolecular structure, with POMs filling in the cages. In compounds 3–5, POMs act as bidentate inorganic bridging ligands to link [Ag(H2DIBA)2]3+ into 1D chains. Their cyclic voltammetric behaviors and electrocatalytic properties were studied. Notably, compound 4 exhibits amperometric sensing performance toward BrO3−. The organic dye pollutant removal behaviors of 1–5 were explored. In addition, the antibacterial/antifungal activities and photoluminescence properties of 3–5 were also investigated. [ABSTRACT FROM AUTHOR]

Electrochromic supercapacitors have received extensive attention owing to their ability to combine electrochromism and energy storage properties. In this paper, a bifunctional electrode material based on Preyssler‐type tungstophosphate (P5W30), polyelectrolyte poly(allylamine hydrochloride) chain (PAH) modified by the iron complex (Fe(phen)3) was synthesized by Layer‐by‐Layer method (LbL). Compared with the film without PAH, the composite film displays large optical contrast (35.17 %), fast response time (2.49/0.90 s for coloring/bleaching), great coloration efficiency (94.73 cm2 ⋅ C−1) and high specific capacitance (10.45 mF cm−2). Moreover, the good cycling stability (83.66 % retention of the original optical modulation after 1500 cycles, capacity retention rate is 91.46 % after 500 cycles) is achieved. In addition, the composite film is also able to visually detect the energy storage level through reversible and rapid color changes, and further use it to assemble device. This work provides an promising candidate for electrochromic and energy storage devices. [ABSTRACT FROM AUTHOR]

A W18O49/[PEI/P5W30]20 film modulated for visible and near infrared light was prepared by a layer-by-layer method on an FTO glass substrate, and had a significant coloration efficiency (149.78 cm2 C−1), fast response time (2.62 and 0.94 s at 650 nm, and 1.98 and 1.92 s at 1167 nm, respectively), and good cycling stability (500 cycles) in 0.5 M AlCl3 electrolyte. Furthermore, the W18O49/[PEI/P5W30]20 film was successfully assembled into an electrochromic device, which can realize color reversibility conversion under a small voltage. Overall, the experimental results showed that W18O49/[PEI/P5W30]20 film preparation allows the production of an electrochromic film for next-generation smart windows, which are able to evenly control the solar light and heat gain in buildings. [ABSTRACT FROM AUTHOR]

A W18O49/[PEI/P5W30]20 film modulated for visible and near infrared light was prepared by a layer-by-layer method on an FTO glass substrate, and had a significant coloration efficiency (149.78 cm2 C−1), fast response time (2.62 and 0.94 s at 650 nm, and 1.98 and 1.92 s at 1167 nm, respectively), and good cycling stability (500 cycles) in 0.5 M AlCl3 electrolyte. Furthermore, the W18O49/[PEI/P5W30]20 film was successfully assembled into an electrochromic device, which can realize color reversibility conversion under a small voltage. Overall, the experimental results showed that W18O49/[PEI/P5W30]20 film preparation allows the production of an electrochromic film for next-generation smart windows, which are able to evenly control the solar light and heat gain in buildings. [ABSTRACT FROM AUTHOR]

Polyoxometalates (POMs) are considered as an attractive option for electrochromic energy storage (EES) system due to their unique electrochemical feature. Herein, a composite film NW/P2W17/Cu (phen)2 based on Dawson‐type monolacunary POMs K10P2W17O61 (abbreviated as P2W17) and copper complex [CuII (phen)2](NO3)2 (abbreviated as Cu (phen)2) formed on TiO2 nanowire (abbreviated as NW) array substrate was fabricated by hydrothermal process and layer‐by‐layer self‐assembly combination method. This rational designed film NW/P2W17/Cu (phen)2 exhibits excellent tunable multicolor electrochromic behavior and improved pseudocapacitive performance with large optical modulation (43.7% at 600 nm), fast switching time (tc = 2.9 s, tb = 9.5 s), and high volumetric capacitance (228.0 F cm−3 at 0.3 mA cm−2). In the process of charge and discharge, the composite film can realize the transformation from light green to orange, green, and finally to blue‐green color, successfully achieve the bridge between electrochromic behavior and energy storage, and monitor the level of stored energy by color change. This work showed great potential of POMs‐based electrode materials for integrated electrochromism and energy storage applications. [ABSTRACT FROM AUTHOR]

A novel three-dimensional (3D) supramolecular assembly of Standberg-type polyoxometalate and flexible organic molecule (Hbpp)[MoPO]·HO ( 1) [bpp = 1,3-bis(4-pyridyl)propane] has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR spectra, elemental analysis and thermogravimetric analysis (TGA). X-ray analyses show that compound 1 represent a twofold interpenetrating 3D supramolecular architecture constructed of Standberg-type polyoxometalate and bpp molecular through the hydrogen bonds as well as electrostatic interactions. [ABSTRACT FROM AUTHOR]

Abstract: A new monomeric heteropolymolybdoarsenate (H2NCNH2NH2)8(H3O)2[Mn2(AsVMo9O33)2]·9H2O (1), has been synthesized in aqueous solution and characterized by elemental analysis, IR spectroscopy, thermal gravimetric analysis, and single-crystal X-ray diffraction. 1 resembles sandwich-type complexes and involves the coordination of two transition metals to two [AsVMo9O33]7− fragments, which derive from the B-β-Keggin structure. The magnetic properties of 1 have been studied by measuring its magnetic susceptibility in the temperature range 2.0–300.0K, indicating the existence of antiferromagnetic interactions. [Copyright &y& Elsevier]

Abstract A nanocomposite film containing Preyssler-type polyoxometalate (POM) K 12.5 Na 1.5 [NaP 5 W 30 O 110 ] (P 5 W 30) and TiO 2 nanowire arrays was fabricated by combining hydrothermal and Layer-by-Layer (LbL) self-assembly methods. Compared to individual TiO 2 nanowire and P 5 W 30 thin film, the composite films exhibits improved electrochromic properties of higher optical modulation (46.03% at 650 nm), faster switching times (7.03 s for coloration and 2.55 s for bleaching), outstanding coloration efficiency (163.4 cm2/C at 650 nm) and good cycling stability. Obviously, the enhancement of electrochromic performances can be attributed to the synergetic contribution from P 5 W 30 and TiO 2 , which displays large real active area to support larger Li+ ion insertion and extraction sites. These advantages can make the nanocomposite film become a promising candidate for potential application in electrochromic devices. Graphical abstract A nanocomposite film containing Preyssler-type polyoxometalate K 12.5 Na 1.5 [NaP 5 W 30 O 110 ] (P 5 W 30) and TiO 2 nanowire arrays was fabricated by combining hydrothermal and Layer-by-Layer (LbL) self-assembly methods. The composite film exhibits improved electrochromic properties because of the synergetic contribution from P 5 W 30 and TiO 2. These advantages can make the nanocomposite film become a promising candidate for potential application in electrochromic devices. Unlabelled Image Highlights • Nanocomposite film based on Preyssler-type polyoxometalate and TiO 2 nanowires • Smart combination of hydrothermal and LbL methods • Improved electrochromic properties of higher optical modulation and outstanding coloration efficiency [ABSTRACT FROM AUTHOR]

Two new Keggin-based copper-organic complexes were synthesized by using a flexible nitrogen heterocyclic carboxylic acid ligand 1-(4-carboxylbenzyl-3-(pyrazine-2-yl)pyrazole. They display good electrocatalysis activities toward H 2 O 2 , BrO 3 - and NO 2 – and ascorbic acid and can be used as nitrite amperometric sensors. In addition, their activity of photocatalytic degradation of MB and RhB have also been investigated. [Display omitted] • Two new Keggin-based copper-organic complexes were synthesized by using a flexible nitrogen heterocyclic carboxylic acid ligand 1-(4-carboxylbenzyl-3-(pyrazine-2-yl)pyrazole. • Helical chains can be found in compound 2. • They display good electrocatalysis activities toward H 2 O 2 , BrO 3 - and NO 2 – and ascorbic acid and can be used as nitrite amperometric sensors. • Their activity of photocatalytic degradation of MB and RhB has also been investigated. By regulating the initial reactant molar ratio, two new Keggin-based copper-organic complexes formulated as [Cu 2 (H 2 O)(L) 2 (HL) 2 ](HPMo 12 O 40)·2H 2 O (1) and [Cu 4 L 4 (H 2 O) 2 ](H 3 PMo 12 O 40) (2) (HL = 1-(4-carboxylbenzyl)-3-(pyrazine-2-yl)]pyrazole) have been synthesized triumphantly under hydrothermal conditions. Single crystal X-ray diffraction analyses show that compound 1 is a 3D supramolecular structure constructed by 1D metal–organic chains [Cu 2 (H 2 O)(L) 2 (HL) 2 ] n 2n+ and PMo 12 anions via hydrogen bonds. Compound 2 is a 2D [Cu 2 L 2 (H 2 O)] n coordination polymeric network containing left and right helical chains. By hydrogen bonding interactions between adjacent [Cu 2 L 2 (H 2 O)] n networks and PMo 12 anions, the 2D network extends to a 3D supramolecular structure. The two compounds can not only photocatalytic degrade methylene blue and Rhodamine B, but also have electrocatalytic reduction of H 2 O 2 , BrO 3 - and NO 2 – and oxidation of ascorbic acid. Moreover, their electrochemical sensing properties have also been studied. These results suggest compounds 1 and 2 can be used as multifunctional materials. [ABSTRACT FROM AUTHOR]

A novel 3D supramolecular compound assembled from Strandberg-type polyoxometalate and benzimidazole [Hbiz] 5 [HMo 5 P 2 O 23 ]·5H 2 O ( 1 , biz = benzimidazole) was synthesized with a convenient aqueous solution method and structurally characterized through single-crystal X-ray diffraction, elemental analysis, IR and UV–vis spectrum analyses. Single-crystal X-ray analysis revealed that the title compound crystallized in the monoclinic system space group P 2 1 / c with a = 11.415(2), b = 33.311(7), c = 13.941(3) Å, β = 99.2279(3)°, V = 5232.0(18) Å 3 , and Z = 4. Compound 1 was composed of one [HMo 5 P 2 O 23 ] 5 − polyanion, five protonated biz cations, and five crystal water molecules; it displayed a 3D supramolecular structure through electrostatic attraction, hydrogen bonding, and π–π interactions. The experiment on anti-tumor activities in vitro showed that compound 1 inhibited human neuroblastoma SHY5Y cells and demonstrated dose dependency and selectivity. [ABSTRACT FROM AUTHOR]

Solid lipid nanoparticles (SLNs), prepared with physiologically compatible high melting point lipids as skeleton materials, are the carriers of a new drug delivery system with great development prospects. In this paper, we have successfully encapsulated two types of polyoxometalates (POMs) with SLNs to improve their biological efficacy. The in vitro antitumor activity of POMs in its free and nano-encapsulated forms was investigated using the MTT assay that was carried out on three types of human cancer cells, HeLa, HepG2 and SHY5Y. The results represent the enhancement of antitumor activity of POMs due to its encapsulation in SLNs. Moreover, the interactions of two types POMs towards ctDNA and bovine serum albumin have been illustrated by electron absorption spectroscopy. • We have successfully encapsulated two types of POMs with solid lipid nanoparticles. • Nanoparticle size and good biocompatibility of SLNs may enhance the antitumor activity of POMs. • An interaction occurred between POMs with ctDNA and BSA. Polyoxometalates (POMs) have shown remarkable antitumor activity. However, the utilization of POMs is limited due to its poor water solubility, low bioavailability, thermodynamics and kinetic instability at physiological pH in water. In order to overcome these drawbacks, POMs with antitumor activity, [Na 10 (H 2 W 12 O 42)]·26H 2 O and [Hbiz] 5 [HMo 5 P 2 O 23 ·5H 2 O, were encapsulated within solid lipid nanoparticles (abbreviated as NaW 12 -SLNs and P 2 Mo 5 -SLNs, respectively), which have been prepared and structurally characterized by Fourier transform infrared (FT–IR) spectroscopy, UV–Vis spectroscopy, X-ray diffraction (XRD), dynamic light scattering (DLS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images. The results show that POMs retain its parent structure after entrapped by SLNs. The in vitro antitumor activity of NaW 12 and P 2 Mo 5 in its free and nano-encapsulated forms was investigated using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetra-zolium bromide (MTT) assay that was carried out on three types of human cancer cells, HeLa, HepG2 and SHY5Y. The results represent the enhancement of antitumor activity of POMs due to its encapsulation in SLNs. Moreover, the interactions of two types POMs towards ctDNA and bovine serum albumin (BSA) have been illustrated by electron absorption spectroscopy. [ABSTRACT FROM AUTHOR]