A series of tetrabutyl ammonium (TBA) salts V-included Keggin-type polyoxoanions with W (TBA4PW11V1O40 and TBA5PW10V2O40) Mo (TBA4PMo11V1O40 TBA5PMo10V2O40) as addenda atoms were prepared using a hydrothermal method. These synthesized materials characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-Vis diffuse reflectance (DRS UV-Vis), thermogravimetric an...

Reaction products of titanium(IV) sulfate in HCl-acidic aqueous solution with the dimeric species linked through three intermolecular Ti-O-Ti bonds of the two trititanium(IV)-substituted α-Keggin polyoxometalate (POM) subunits are described. Two novel titanium(IV)-containing α-Keggin POMs were obtained under different conditions. One product was a dimeric species through two intermolecular Ti-O...

Mixed-addenda vanadium substituted polyoxometalate supported on anatase TiO2 crushed nano leaf was synthesized by an unusual reaction with titanium tetraisopropoxide at 100 ºC via sol–gel method under oil-bath condition. The materials characterized by XRD, TEM,  IR and UV–vis  techniques.  In  the  present  work,  efficient  oxidative  of  thiols  with  polyoxometalate-TiO2/hydrogen  peroxide  ...

The efficacy of a variety of polyoxometalate anions in selectively precipitating the infectious isoform of the prion protein (PrPSc) over the normal, cellular protein (PrPC) was tested as a means of improving the sensitivity of a conformation-dependent immunoassay (CDI). Experiments utilizing neutralized aqueous solutions containing MgCl2.6H2O and Na2H[PW12O40] (1) indicated that use of the for...

In the work reported in this paper, we demonstrate that Ag–Keggin ion colloidal particles are excellent templates for the synthesis of organized assemblies of silver nanoparticles, wherein the Keggin ion host plays the role of a UV-switchable reducing agent. More specifically, we investigate the formation of aqueous colloidal particles of Ag ions complexed with phosphotungstate (PW12O40) 32 Keg...

The rational self-assembly of mono-lacunary Keggin clusters with 4d and 4f metal salts via a conventional method has yielded two novel polyoxometalate-based 4d-4f heterometallic compounds containing lacunary Keggin anions connected to ten metal atoms: {[Ag{Ag2(H2O)4}{Ln(H2O)6}2H ⊂ {SiW11Ln(H2O)4O39}2]·nH2O (Ln = Ce and n = 7 for 1, Ln = Pr and n = 3 for 2). Their structures were determined by s...

A Keggin-type polyoxometalate (Cs(1.5)H(1.5)PW(12)O(40))-supported Pd catalyst is efficient for the direct synthesis of H(2)O(2) from H(2) and O(2) in the absence of any acid or halide additives under atmospheric pressure.

Ru nanoparticles loaded on a Keggin-type polyoxometalate (Cs(3)PW(12)O(40)), which did not possess strong intrinsic acidity, efficiently catalysed the conversions of cellobiose and cellulose into sorbitol in water medium in H(2) at ≤433 K. The Brønsted acid sites generated in situ from H(2) have been demonstrated to play a key role in the formation of sorbitol.

An efficient and improved procedure for the synthesis of 1,4-diazepine and 1,5-benzodiazepine derivatives via the reaction of ketimine intermediates with aldehydes in the presence of Keggin-type heteropolyacids (HPAs) was developed. High yields and short reaction times were obtained for both electron-releasing and electron-withdrawing substituted 1,4-diazepine  and 1,5-benzodiazepines derivatives.