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A case of organic–inorganic hybridized phosphotungstate modified using aromatic organophosphonic acid, K4Na4H11[KCo2(H2O)10P4W24O92{(PhPO)2}]·48H2O (1), was successfully synthesized in conventional aqueous solution. The prominent structural feature is that the total structure of [KP4W24O92{(PhPO)2}]23− resembles a V-shaped structure, which was stabilized by two [Co(H2O)5]2+ ions. Furthermore, it can be connected into a three-dimensional mesh structure using K+ ions. Surprisingly, 1 possesses a remarkably high proton conductivity of 1.59 × 10−2 S cm−1 at 95% RH and 318 K probably due to the fact that its structure contains large amounts of lattice water molecules, coordination water molecules and counter cations. [ABSTRACT FROM AUTHOR]

Two Ni-inserted polyoxotantalates, K5.5Na2H0.5[Ni(H2O)2{NiTa10O30(OH)2}]·21H2O (1) and K6Na4[Ni(en){NiTa10O32}]·22H2O (2, en = ethanediamine), were synthesized in this work. Crystallographic data analyses reveal that 1 and 2 have similar configurations. A minor difference between these two structures is that the {Ni(H2O)2} unit in 1 is replaced by {Ni(en)} unit in 2. Notably, the other Ni in 1 and 2 is located as a heteroatom at the center of the {Ta10} unit, which is reported in POTas for the first time. Moreover, 2 exhibits excellent catalytic performance in transesterification reactions in a preliminary exploration of the catalytic ability of the synthesized POTas. [ABSTRACT FROM AUTHOR]

A wheel-shaped Zr-substituted phosphotungstate, [N(CH3)4]2K16Na10.5H10.5[{Zr(C2O4)2}3(PO4)(P6W39O150)]·45H2O (1), was synthesised from a hexavacant Dawson-type precursor [H2P2W12O48]12−via a conventional solution method. Compound 1 features a wheel-shaped polyanion comprising an annular [P6W39O150]36− cluster supported by a turbine-shaped [{Zr(C2O4)2}3(PO4)]3− fragment, with three oxalate groups covalently anchored to W atoms. Compound 1 was systematically characterized by IR, UV, PXRD, TGA and 31P NMR spectra. The 31P NMR spectra over time were monitored to verify the stability of 1 in aqueous solution. This compound possesses remarkable proton conductive behavior with a high conductivity of 1.18 × 10−2 S cm−1 at 368 K. [ABSTRACT FROM AUTHOR]

An unclassical structure of {Ru(C6H6)}‐based polyoxometalate, Cs6H4[Te2Mo12O46{Ru(C6H6)}] ⋅ 16.5H2O (1), has been successfully constructed from {Te2Mo12O46}‐type heteropolymolybdate and {Ru(C6H6)} group, which structure type was discovered for the first time. Compound 1 not only possesses strong light‐harvesting ability, but also exhibits high carrier separation efficiency and lower charge transfer resistance. Under visible light irradiation, compound 1 displayed excellent catalytic activity and circularity in the conversion of benzyl alcohol to benzaldehyde (yield=94 %; turnover number=500; turnover frequency=20.8 h−1). Finally, the electron paramagnetic resonance measurement and energy level matching analysis provide theoretical basis for the derivation of the reaction mechanism. [ABSTRACT FROM AUTHOR]

The synthesis of highly efficient visible‐light‐responsive photocatalysts is fundamental to solving the problems of low efficiency and poor selectivity in photocatalytic organic synthesis reactions. We synthesized a crystalline polyoxometalate @metal‐organic framework material {Zn4(H2O)8[Ir(ppy)2(dcbpy)]4[SiW12O40]} ⋅ 4H2O (Ir−SiW) by self‐assembly of Ir metalloligands with POMs. The introduction of Ir metalloligands extends the light absorbing range to visible light, improving the efficient utilization of solar energy. The transfer of photogenerated electrons from Ir metalloligands to SiW12 was observed under visible light irradiation, which boosted the carrier separation efficiency. The synergistic effect of the two components increased the photocatalytic thioether oxidation activity, and the product methyl phenyl sulfoxide for 2.5 h under visible light irradiation (λ >400 nm) reached 99.5 %, which was higher than those of other POM‐based photocatalysts. Meanwhile, the yield of methyl phenyl sulfoxide was still higher than 97 % after three cycles, demonstrating the high stability and reusability of Ir−SiW. [ABSTRACT FROM AUTHOR]