Assemblies based on the directing effect of non-classical W18 anionic clusters and the rod-like trans-1,2-di-(4-pyridyl)-ethylen (bpe)

Controlled Assembly of a Dawson-like Antimoniotungstate-Supported Trefoil-type Trimer with Good Proton Conductivity Performance

With the excellent properties of POM in the field of proton conductivity, the preparation of POM-based proton-conductive materials has burst into life. Herein, an unprecedented Sb-templated all-inorganic trimer Na8H18.64[(SbW14O52)3(Sb2W6.12Ru5.88O18)]·85H2O (1), which is based on tetravacant Dawson-like [SbW14O52]17- blocks and exhibits a trefoil type with D3 symmetry, has been successfully designed and synthesized by the assembly of simple materials with a one-pot hydrothermal method under acidic conditions. Also, compound 1 is systematically characterized by single-crystal X-ray diffraction, PXRD, ESI-MS, IR spectroscopy, UV-vis, elemental analysis, and TGA. Crystal structure data analysis demonstrates that compound 1 is constructed by a hexagonal prismatic heterometallic {Sb2W6.12Ru5.88O18} core and three equivalent {SbW14} units bridged through μ2-O atoms in periphery. Subsequently, further property experiments show that compound 1 exhibits high proton conductivity with a conductivity value (σ) of 3.07 × 10-2 S cm-1 at 75 °C and 80% relative humidity (RH). The activation energy of compound 1 evaluated by the Arrhenius plots is 0.22 eV, which indicates that the Grotthuss mechanism is dominant during the process of proton transfer.

Two novel Dawson-like tungstoantimonates with difunctional photocatalytic and magnetic properties

Two novel inorganic-organic hybrids containing the pyramidal SbO₃ group in Dawson-like POMs based on an organic ligand with different coordination modes, namely {Ni(phen)₃}₃[SbW₁₈O₆₀]·(H₃O)₃·7H₂O (1) and [Cu^I(phen)(H₂O)₃]{[Cu(phen)₂(H₂O)₂]₂[SbW₁₈O₆₀]}·2H₂O (2) (phen = 1,10-phenanthroline), have been synthesized. The catalytic property of compound 1 was studied as the first case for an {M₁₈} cluster containing the pyramidal SbO₃ group. Remarkably, compound 1 has excellent photocatalytic activity for RhB degradation and the probable mechanism of degradation was discussed. Additionally, the 2D-IR correlation spectra (2D-IR COS) under magnetic perturbation were recorded to analyze the magnetic properties of compound 1. The 2D-IR COS under thermo perturbation were recorded to verify the presence of H-bonding interactions.