A study of solution species generated during the formation of 12-heteropoly oxometalate catalysts

Heteropolyacids as anode catalysts in direct alkaline sulfide fuel cell

“…The absence of the characteristic bands for any deformed structures, such as lacunary Keggin structure (e.g. PMo 11 ) [26,27], further confirms the Keggin structure of the HPA samples. Even more clearly, the preservation of the Keggin structure was identified from the EDX analysis, in which the atomic ratio of addenda atom (Mo and W) to hetero atom (P and Si) turned out to be close to theoretical value of 12 for all the HPA samples.…”

Stability investigation of some heteropolyoxotungstate and heteropolyoxomolybdate salts in buffer solutions

“…Dodecatungstophosphoric acid (H 3 PW 12 O 40 , abbreviated as HPW) [14], tyrosine dodecatungstophosphate ((HTyr) 3 [15], and ornithine dodecatungstosilicate ((HOrn) 4 [SiW 12 O 40 ] abbreviated as (HOrn)SiW) [16] were synthesized by previously reported methods and confirmed by FT-IR spectroscopy, elemental analysis, and X-ray fluorescence. All reagents and solvents were purchased from Merck Company and used without further purification.…”

“…Only a few reports are available on degradation of POMs in aqueous solutions as mentioned in literature [9][10][11]. It can be generally concluded that the hydrolytic stability of POMs depends on the anion structure, the nature of the heteroatom, the addenda atom which comprises the anion, as well as on the experimental conditions [12,13].…”

Polyoxotungstates Reduce the β-Lactam Resistance of Methicillin-Resistant Staphylococcus aureus

“…Interestingly, WO 4 2-has the unique feature that this oxoanion polymerizes easily with itself or with other oxoanions such as PO 4 3-, forming a POT [75,[27][28][29][30] 4 2-+ 3H 2 O, and the major polyanion present in the solution is PW 11 [27][28][29][30]. Although PW 11 is decomposed completely at pH > 8, 80~90% of this compound still remains as [PW 11 O 39 ] 7-below pH 7.2 [78,79]. It therefore seems natural to investigate the biological and biochemical effects of WO 4 2-and PW 11 , both of which are representative of the tungsten compounds present around physiological (neutral) pH.…”