Electroreduction-Driven Formation and Connectivity of Polyoxometalate Coordination Networks.

We present the synthesis of metal oxide coordination networks based on Preyssler-type polyoxoanions ([NaPWO] and [NaPMoWO]) bridged with metal-aquo complexes ([M(HO)], M = Co, Ni, Zn, Y), induced by electrochemical reduction. Networks bridged with first-row transition metals are isostructural with a previously reported Co-bridged structure, while the Y-bridged structure is new. All networks feature an uncommon binding motif of the metal cation to the oxygen atoms at cap positions, which we hypothesize is due to increased electron density at the cap upon reduction.

PEG-Infiltrated Polyoxometalate Frameworks with Flexible Form-Factors.

We present the synthesis of metal oxide frameworks composed of the Preyssler anion, [NaPWO], bridged with transition-metal cations and infiltrated with polyethylene glycol. The frameworks can be dissolved in water to form freestanding rigid or flexible films or gels. Powder X-ray diffraction shows that all form-factors maintain the short-range order of the original crystals.