Nanocomposite multilayer film of a ruthenium metallodendrimer and a Dawson-type polyoxometalate as a bifunctional electrocatalyst

A pentaerythiritol-based metallodendrimer with four ruthenium(II) terpyridine units (RuDen) and a Dawson-type phosphotungstate, P(2)W(18)O(62)(6-) (P(2)W(18)) are immobilized on a glassy carbon electrode to form multilayered self-assemblies by layer-by-layer deposition based on electrostatic interaction. The (P(2)W(18)\RuDen) multi-layer films have been investigated with UV-visible spectrometry, cyclic voltammetry, and TappingMode atomic force microscopy. They showed a bifunctional electrocatalytic capability, namely, iodate reduction and arsenite oxidation.