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The composite materials were prepared by 90 wt.% tungstovanadophosphoric heteropoly acids with Dawson structure (H7P2W17VO62·nH2O and H9P2W15V3O62·nH2O, abbreviated as P2W17V and P2W15V3), 5 wt.% silica gel (SiO2) and 5 wt.% organic polymers (polyvinylpyrrolidone, PVP or polyethylene glycol, PEG). The products were characterized by the infrared (IR), X-ray powder diffraction (XRD) and electrochemical impedance spectroscopy (EIS). EIS measurements show that the conductivity values PVP/P2W17V/SiO2, PVP/P2W15V3/SiO2 and PEG/P2W15V3/SiO2 are 1.89 × 10−2, 2.32 × 10−2 and 2.67 × 10−2 S cm−1 at 26 °C and 75% relative humidity, which increase with higher temperature. They exhibit low activation energies of 16.12, 16.85 and 14.02 kJ mol−1 for proton conduction, respectively. The mechanisms of proton conduction of the composite materials are also proposed. [ABSTRACT FROM AUTHOR]

The ruthenium-substituted polyoxometallic acid H[Ru(HO)FeWO]·18HO was synthesized by stepwise acidification and stepwise addition of solutions of the component elements, and an ion-exchange-cooling method. The product was characterized using inductively coupled plasma spectrometry (ICP), Infrared Spectroscopy (IR), Ultraviolet Spectroscopy (UV), and X-ray diffraction (XRD). The results show that this complex has the Keggin structure. The determination of the thermal stability and proton conductivity of this polyoxometallic acid was carried out by a thermogravimetric-differential thermal analysis (TG-DTA) and electrochemical impedance spectroscopy (EIS). [ABSTRACT FROM AUTHOR]

A new solid high-proton conductor, H[Ga(HO)PWO]·18HO, a substituted heteropoly acid with Dawson structure, has been synthesized by the degradation/ion-exchange/freezing method. The product was characterized by potentiometric titration, chemical analysis, IR, UV, XRD and TG-DTA. Complex impedance measurements show a high conductivity (5.44×10 S/cm at 50°C), with an activation energy for proton conduction of 36.04 kJ/mol. The mechanism of proton conduction is the Vehicle mechanism. [ABSTRACT FROM AUTHOR]

Abstract: A new solid high-proton conductor, heptadecatungstovanadodiphosphoric heteropoly acid H7P2W17VO62·28H2O with Dawson structure was synthesized by the stepwise acidification and the stepwise addition of element solutions. The optimal proportion of component compounds in the synthesis reaction was given. The product was characterized by chemical analysis, potentiometric titration, IR, UV, XRD, 31P NMR, TG-DTA and electrochemical impedance spectroscopy (EIS). The results indicate that H7P2W17VO62·28H2O possesses the Dawson structure. EIS measurements show a high conductivity (3.10×10−2 Scm−1 at 26°C and 75% relative humidity), with an activation energy of 32.23kJmol−1 for proton conduction. The mechanism of proton conduction for this heteropoly acid is Vehicle mechanism. [Copyright &y& Elsevier]

Abstract: In this work, the polyvinyl alcohol (PVA) films composited with decatungstomolybdovanadogermanic heteropoly acid (HPA) were prepared. Infrared (IR) spectra revealed that the Keggin structure characteristic of the GeW10MoVO40 5− anion was present in PVA films. At room temperature (20°C), the conductivity of the samples of different HPA content increased from 3.16×10−3 to 1.22×10−2 Scm−1. The results indicated that they are new kind of excellent high-proton conductor. [Copyright &y& Elsevier]

In this work, the polyvinyl alcohol (PVA) films composited with molybdotungstovanadogermanic heteropoly acid were prepared. Infrared spectra (IR) revealed that the Keggin structure characteristic of the GeMo2W9VO405− anion was present in PVA films. At room temperature (20 °C), the conductivity of the samples of different HPA content increased from 2.46×10−3 to 9.92×10−3 S cm−1. The results indicated that they are new kind of excellent high-proton conductor. [Copyright &y& Elsevier]

A proton conductor solid electrolyte tri-vanadium-substituted tungstosilicic acid H7SiW9V3O40·9H2O with Keggin structure was prepared by the stepwise acidification and the stepwise addition of element solutions. The product is characterized by Infrared (IR) spectroscopy, UV spectrum and X-ray powder diffraction (XRD). Its proton conductivity has been measured by the electrochemical impedance spectroscopy (EIS) in the temperature region 18–58°C and 50% relative humidity. The conductivity increases from 2.05×10−3 Scm−1 at 18°C to 8.11×10−3 Scm−1 at 58°C, with an activation energy of 26.69kJmol−1 for proton conduction. The conductive mechanism is Vehicle mechanism. [ABSTRACT FROM AUTHOR]

• Ar / Pr SO 3 H–Si(Et)Si nanotubes are prepared by swollen P123-F127 micelle-templating route. • As-prepared nanotube catalysts show excellent transesterification and esterification activities. • Brønsted acid nature of nanotube catalysts dominates the activities. • Inner diameter and surface hydrophobicity of the catalysts influence the activities remarkably. • The nanotube catalysts exhibit excellent reusability and stability in both target reactions. Solid acid-catalyzed biodiesel production from inedible oils offers a promising mean to reduce the cost of feedstocks and avoid the competition with edible oil market. Here we demonstrate a series of inner diameter-controlled sulfonic acid functionalized ethyl-bridged-organosilica nanotubes (Ar / Pr SO 3 H–Si(Et)Si) by a toluene swollen mixed Pluronic surfactant micelle-templating co-condensation route for transesterification of tripalmitin or plant oils with methanol to produce fatty acid methyl esters and esterification of glycerol with lauric acid to produce mono- and di-glycerol esters. By combination of superstrong Brønsted acidity, unique hollow tubular nanostructure, excellent porosity properties and hydrophobic surface, the Ar / Pr SO 3 H–Si(Et)Si nanotubes display higher catalytic activity as compared with acidic resin and zeolite. Additionally, the inner diameters and lengths of Ar / Pr SO 3 H–Si(Et)Si nanotubes influence the activity obviously. The Ar / Pr SO 3 H–Si(Et)Si nanotubes also show excellent catalytic reusability, attributing to covalent bonding of Ar / Pr SO 3 H groups within silica/carbon framework and surface hydrophobicity of the catalysts. [ABSTRACT FROM AUTHOR]

Various photocatalysts composed of undecatungstotitanotitanic heteropoly acid (H 4 [Ti(H 2 O)TiW 11 O 39 ]·7H 2 O) loaded on silica (TiW 11 Ti/SiO 2) were prepared by sol-gel method. The TiW 11 Ti/SiO 2 hybrid materials were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and Diffuse reflectance spectra (DRS). The photocatalytic performance was investigated by photocatalytic degradation of brilliant dye X-3B under ultraviolet light irradiation. The TiW 11 Ti/SiO 2 hybrid showed higher photocatalytic activity than pure TiW 11 Ti and TiW 11 Ti + SiO 2 (TiW 11 Ti mixed simply with SiO 2). Among three different loading weights of TiW 11 Ti for the hybrids, the degradation efficiencies of dye X-3B displayed the following order: 45 wt% > 30 wt% > 60 wt%. Unlabelled Image • H 4 [Ti(H 2 O)TiW 11 O 39 ]·7H 2 O loaded on silica were prepared by sol-gel method. • The photocatalytic property of TiW 11 Ti/SiO 2 was studied by degradation of X-3B. • The TiW 11 Ti loading weights of 45 wt% displayed the best degradation performance. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract This study aimed at investigating the potential mechanism of improved transportation of the curcumin loaded D-α-tocopherol polyethylene glycol 1000 succinate coated nanodiamonds system (NDs/CUR/TPGS complexes) using an in vitro Caco-2 cell monolayer model. The core–shell structured NDs/CUR/TPGS nanocomplexes were 196.32 ± 5.76 nm in size, with a high loading efficiency of 81.59 ± 3.42%. Cytotoxicity results suggested that the blank NDs did not induce any serious toxicity on Caco-2 cells even after incubated for 72 h. The cell viability for all the series of CUR loaded preparations was found to follow the sequence of CUR suspension > NDs/CUR > NDs/CUR/TPGS. Confocal laser fluorescence microscopy (CLSM) and flow cytometry system (FACS) studies confirmed that the cellular uptake of NDs could be efficiently enhanced by TPGS decoration. The transport mechanism of NDs/CUR and TPGS coated ones was mainly through an energy dependent, clathrin-mediated and caveolin-mediated endocytosis, and the endocytosis of NDs/CUR was also via macropinocytosis. Furthermore, the P app value (AP-BL) of NDs/CUR and NDs/CUR/TPGS was 2.09- and 3.86-fold higher than that of the CUR suspension. All the results demonstrated that the pharmacological activates and intestinal permeability of CUR across Caco-2 cell monolayer was greatly enhanced by NDs/CUR/TPGS nanocomplexes. Thus NDs could be a promising oral drug delivery platform for improving the intestinal permeability and oral bioavailability of poorly soluble drugs. [ABSTRACT FROM AUTHOR]

Abstract Designing mixed metal oxides with uniform nanostructures as a significant electrode material in energy storage devices is a vital concern for the whole world. But achieving this goal is plagued by many problems such as tedious procedures, hard morphology control and poor conductivities. The NiCo 2 O 4 /NiFe 2 O 4 hollow nanospheres (NSs) are prepared for the first time through a novel one-pot approach. The introduced NiFe 2 O 4 has amazingly improved the electrochemical performance of NiCo 2 O 4 hollow NSs in both Li-ion batteries (LIBs) and supercapacitors (SCs). And the ratio of Fe to Ni plays an important role for the improvement of electrochemical performance. The NiCo 2 O 4 /NiFe 2 O 4 hollow NSs exhibit superior capacity/capacitance values (3795 F g−1 at a current density of 1 A g−1) and fine cycling performances (11.0% specific capacitance decay after 6000 cycles) which can be attributed to the larger specific surface area of hollow NSs and the synergistic effect of two components. This provides a feasible preview of their practical applications. Graphical abstract Image 1 Highlights • The NiCo 2 O 4 /NiFe 2 O 4 hollow nanospheres (∼50–150 nm) are prepared for the first time. • The ratio of Fe to Ni plays an important role for their electrochemical performance. • The energy density of 34.2 Wh/kg at a power density of 1400 W/kg is obtained for SCs. • They deliver a capacity of 1332 mA h g−1 for LIBs at a current density of 2000 mA g−1. [ABSTRACT FROM AUTHOR]

The material (TOAMe)5[SiW11VO40] was synthesized from a heteropoly acid and a simple quaternary ammonium ionic liquid as a new organic-inorganic hybrid material. It has a phase transition and ion conductivity of ∼2.03×10–3 Ω–1 cm–1 at 26°C. [ABSTRACT FROM AUTHOR]

Hybrid polyoxometalate-based inorganic–organic proton conductors formed through Dawson structure heptadecatungstodiphosphoindic heteropoly acid (P 2 W 17 In), polyvinylpyrrolidone (PVP) and silica gel (SiO 2 ), P 2 W 17 In/PVP and P 2 W 17 In/PVP/SiO 2 , have been investigated. These hybrid materials are characterized by IR, XRD and electrochemical impedance spectrum (EIS). The results reveal that, at room temperature (18 °C), and 70% relative humidity (RH), the conductivities of hybrid materials are 1.70 × 10 − 3 S·cm − 1 and 1.82 × 10 − 3 S·cm − 1 , respectively. Their activation energy values are 8.80 kJ·mol − 1 and 15.53 kJ·mol − 1 . Their mechanisms of proton conduction are also proposed. [ABSTRACT FROM AUTHOR]

Two new solid hybrid molecular materials [PyPS]HPWVO and [PyPS]HPWVO have been synthesized from 1-(3-sulfonic group) propyl-pyridine ionic liquid cation and tungstovanadophosphoric anion with the Dawson structure. They were characterized by element analysis, impedance spectroscopy (IS), IR- and UV-spectroscopy. The formation of the hybrid molecular compounds with the Dawson structure was showed. Ion conductivity of [PyPS]HPWVO and [PyPS]HPWVO are 3.99 × 10 and 7.37 × 10 S cm at 18°C and 55% relative humidity respectively. The activation energies of proton conductivity are 28.2 and 26.7 kJ mol respectively. [ABSTRACT FROM AUTHOR]

A novel kind of organic-inorganic material, (TOAMe)[In(HO)PWO] (TOAMe = trioctylmethylammonium), is synthesized as white oily product from polyoxometalate-type ionic liquid with Dawson structure and simple quaternary ammonium ionic liquid. It was characterized by IR, UV, X-ray diffraction, and thermogravimetric-differential thermal analysis. The determination of (TOAMe)[In(HO)PWO] shows that it has a high conductivity with 1.25 × 10 S cm at 24 °C. In addition, its electrochemical properties were also investigated by the cyclic voltammetric studies. And then we released that the indium in the complexes can undergo reduction in dimethylformamide, which is unlikely in the water solution as a simple hydrated ion. [ABSTRACT FROM AUTHOR]

Abstract: A series of one-dimensional Cd x Zn(1−x)S semiconductor alloys were prepared via a hydrothermal method with the assistance of ethylenediamine at 180°C for 12h. The products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, nitrogen adsorption/desorption and Fourier transform infrared techniques. With the value of x increased, the band gap of Cd x Zn(1−x)S semiconductor alloys gradually decreased indicating that catalysts were exchanged to visible-light response. Photocatalytic reduction results showed that Cd0.73Zn0.27S exhibited the highest photocatalytic activity toward photo production of aniline via nitrobenzene reduction under visible irradiation respectively. The reaction mechanism was also discussed. [Copyright &y& Elsevier]

• A series of vanadium-substituted Keggin-type polyoxometalate doped carbon nitride was prepared. • The photocatalytic oxidation property of POM/g-C 3 N 4 was inspected under visible light irradiation. • The synergistic effect facilitated the high photocatalytic oxidation activity of POM/g-C 3 N 4. A series of vanadium-substituted Keggin-type polyoxometalate ((NH 4) 4 [PMo 11 VO 40 ]) doped carbon nitride (POM/g-C 3 N 4) hybrid materials were prepared by using green dipping method and characterized by FTIR, XRD, and DRS. Their photocatalytic oxidation performance was investigated by degradation of different dye pollutants under visible light irradiation. In different composition, POM/g-C 3 N 4 (1:3) exhibited the best photocatalytic activity compared with POM, g-C 3 N 4 , POM/g-C 3 N 4 (1:1) and POM/g-C 3 N 4 (1:5). The synergistic effect of POM and g-C 3 N 4 in the hybrid facilitated its high photocatalytic capability. [ABSTRACT FROM AUTHOR]

In article number 1805893, Zikang Tang, Chun Cheng, and co‐workers report a method of synthesis of carbon nanotube‐based nanocomposites. MXene nanoflakes, hexagonal molybdenum nitrides, are introduced into a boron, nitrogen co‐doped carbon nanotube matrix by pyrolysis of polyoxometalates and urotropine. The growth of MXenes is induced by urotropine while the carbon nanotube matrixes confine the overgrowth of the nanoflakes. The nanocomposite exhibits outstanding electrocatalytical performance for hydrogen production from seawater. [ABSTRACT FROM AUTHOR]

The Keggin structure and its amorphous phase were detected in the title material. The proton conductivity of the PVP/H5SiW11VO40 hybrid material is 1.39×10–2 S cm–1 at 18°C or 1.78×10–2 S cm–1 at 59°C and 50% relative humidity, and its activation energy is 11.34±0.03kJ mol–1. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of an indium-substituted quaternary heteropoly acid with a Keggin structure, H4[In(H2O)PW9Mo2O39]·11H2O (PMo9W2In), is reported. At 18 °C under 80% relative humidity, PMo9W2In displays protonic conductivity of 2.32 × 10-4 S cm-1 with an activation energy of 35.52 kJ mol-1, indicating that it is a potential solid protonic conductor following the vehicle mechanism. Its conductivity increases with temperature in the measured temperature range.

Despite that either non-covalent or covalent attachment of hydrophilic polymers or surfactants onto nanodiamonds (NDs) could overcome the shortcomings of being a drug delivery system, it is hard to draw a definite conclusion which strategy is more effective. Hence, with the purpose of comparing the influence of different coating approach of NDs on the oral delivery efficiency of water-insoluble model drug curcumin (CUR), NDs were firstly modified with D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) via non-covalent or covalent conjugation method, and then loaded with CUR (CUR@NDs-COOH/TPGS or CUR@NDs-TPGS). In comparison with the core-shell-structured CUR@NDs-COOH/TPGS, CUR@NDs-TPGS were irregular in shape with dense TPGS film, and exhibited smaller size, more negatively potential, and higher drug loading efficiency. The covalent connection group also showed higher anti-cancer activity, cellular uptake, and permeability through the Caco-2 cell monolayers, as well as favorable distribution, penetration, and retention in rat intestines. The oral bioavailability study in rats demonstrated that CUR@NDs-TPGS showed significantly greater C max and AUC 0-t in contrast with CUR suspension and the TPGS-coated ones, respectively. The findings illustrated that covalent grafting TPGS onto the surface of NDs possesses better efficacy and biocompatibility on oral delivery of poorly soluble drug CUR than pristine and non-covalent coated nanoparticles.

Spiro-OMeTAD is currently the most widely used hole transport material for the preparation of high-performance perovskite solar cells (PSCs), usually requiring the addition of additives to achieve the desired electronic conductivity. However, the quality of the film is degraded owing to the addition of additives. Holes and defects can be observed, and the dispersion of the additives are uneven inside. Here, a copper coordination polymer, Cu-bix, with matching energy level and fluorescent properties was screened for use as an additional additive to dope Spiro-OMeTAD. The doping of Cu-bix effectively improved the dispersion state of the additives in the hole transport layers and alleviated the aggregation of LiTFSI (lithium bis(trifluoromethanesulfonyl)imide) or/and lithium salt complexes in the film. Owing to better dispersion of the additives, Spiro-OMeTAD was more fully and uniformly oxidized whereas the possibility of charge recombination was reduced in the devices. Furthermore, the flat and tightly bonded film layer obtained by optimization of the doping amount can efficiently transfer holes from the perovskite layers to the hole transport layers. Possible interaction mechanisms between additives and the copper coordination polymer are proposed and discussed. The resulting power conversion efficiency (PCE) for Cu-bix-doped PSCs was improved from 16.52 % to 18.47 % compared to the pristine devices, and this type of PSCs also showed a long stability in air owing to the increased hydrophobicity of the Cu-bix-based hole transport layers., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)