A series of Dy Er-polyoxometalates (POMs) were successfully synthesized and characterized well by various physicochemical analysis. The structurally isolated compounds exhibit three characteristic emissions at 480 nm (blue, F → H transition), 573 nm (yellow, F → H transition), and 663 nm (red, F → H transition) whose luminescent color coordinates appear in the near-white area in the CIE 1931 chromaticity diagram. Time-resolved emission spectroscopy was used in Dy Er-POM to further authenticate energy transfer from the photoexcitation O → M ligand to the metal charge-transfer state of phosphotungstate components to active Dy/Er ions and energy transfer between Dy ion and Er ion via intramolecular energy transitions. The relative emission intensity of ∼32%, ∼53%, and ∼85% for Dy-POM, DyEr-POM, and DyEr-POM respectively, were obtained under 300 min of UV irradiation, which indicates better photostability of DyEr-POM. Furthermore, Dy Er-POM samples can emit macroscopic white light under blue irradiation.

A simple and cost-effective approach has been explored to design monophasically pure and facet-controlled CoS2 octahedra with intrinsic carbon for enhanced oxygen reduction electrocatalysis under acidic conditions.

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A polyoxometalate–ionic polymer composite was utilized as highly stable and efficient catalyst for high performance Li–S battery cathode with high utilization of sulfur and capacity retention.

The composite of polyoxometalate [WZn3­(H2O)2­(ZnW9O34)2]12– (ZnPOM) with polyvinylidene-butyl-imidazolium cation (PVIM) and oxidized carbon nanotubes (OCNT) as non-noble metal bifunctional catalyst has been studied for oxygen-depolarized cathode (ODC) and Cl2 evolution in HCl electrolysis for the first time. The cyclic voltammetry and rotating disk electrode measurement analysis reveals superior activity of the composite as bifunctional catalyst for ODC and Cl2 evolution. Chronoamperometric experiments show high long-term stability, comparable to the state-of-art catalyst, even under multiple shutdown to open circuit potential. X-ray photoelectron spectroscopic studies after electrolysis (48 h) confirms no degradation of the composite and, hence, appears to be stable. Scanning electrochemical microscopy (SECM) measurements indicate that, even after 72 h of electrolysis, the composite retains high activity, similar to fresh composite.