INDIRECT SYNTHESIS OF KEGGIN POLYOXOMETALATES WITH TUNGSTEN AND VANADIUM ADDENDA

In this paper we aim to synthesize HxPW12-xVxO40 (x=1, 2, 3) indirectly, starting from lacunar Keggin compounds. H4PW11VO40·10H2O was obtained from monolacunary K7[PW11O39] by the addition of vanadates under controlled conditions of pH and temperature, while H6PW9V3O40·16H2O was synthesized from the trilacunar species Na9[HPW9O34]·11H2O in reaction with vanadate. For all prepared POM acids, the synthesis yields were very good and compounds with vanadium atoms were obtained in adjacent positions. Elementary analyzes, basicity determination, thermogravimetry, UV-VIS and FT-IR spectral data supported structure and composition HxPW12-xVxO40 (x = 1, 2, 3). HxPW12-xVxO40 (x=1, 2, 3) structure and composition.