Nanoconfinement of polyoxometalates in cyclodextrin: computational inspections of the binding affinity and experimental demonstrations of reactivity modulation.

Chaotropic polyoxometalates (POMs) form robust host-guest complexes with γ-cyclodextrin (γ-CD), offering promising applications in catalysis, electrochemical energy storage, and nanotechnology. In this article, we provide the first computational insights on the supramolecular binding mechanisms using density-functional theory and classical molecular dynamics simulations. Focusing on the encapsulation of archetypal Keggin-type POMs (PWO , SiWO and BWO ), our findings reveal that the lowest-charged POM, namely PWO spontaneously confines within the wider rim of γ-CD, but BWO does not exhibit this behaviour.

Clustering Six Electrons within "Dawson-Like" Polyoxometalate: An Open Route toward Its Post-functionalization.

Super-reduction of polyoxometalates (POMs) in solution is of fundamental interest for designing innovative energy storage systems. In this article, we show that the "Dawson-like" POM can undergo a disproportionation process during its massive electron uptake, leading to species containing three metal-metal bonds as evidenced by X-ray diffraction, multi-nuclear magnetic resonance spectroscopy ( H and W NMR), extended X-ray absorption fine structure (EXAFS), UV/Vis, and voltammetry techniques. This result indicates that electron storing within metal-metal bonds is not a unique property of Keggin-type POM as postulated since the 70s.

Making Heterometallic Metal-Metal Bonds in Keggin-Type Polyoxometalates by a Six-Electron Reduction Process.

Polyoxometalates (POMs) represent a promising class of molecular electron reservoirs. However, their multielectron reduction gives rise to intricate physical-chemical phenomena that must be fully understood for their future use in energy-storage devices. Herein, we show that bulk electrolysis of the archetypal Keggin-type POM [Si(WMoO)(WO)] in aqueous solution leads to the six-electron-reduced derivative [Si(WMoO(HO))(WO)] (notated ) in which the mixed-metal triad acts as a storage unit for six electrons and six protons.