Preparation and characterization of decatungstomolybdoniobogermanic heteropoly acid H5[GeW10MoNbO40]·20H2O

The decatungstomolybdoniobogermanic heteropoly acid H5[GeW10MoNbO40]·20H2O has been prepared for the first time. The optimal proportion of the solutions of the component and the pH of the synthesis reaction are given. The product was characterized by chemical analysis, conductometric and potentiometric titration, IR, UV, XRD, 183W NMR and TG-DTA. The IR, UV, XRD and 183W NMR indicate that H5[GeW10MoNbO40]·20H2O possesses the Keggin structure. The TG-DTA curve shows the sequence of water loss in the acid, the amount of the loss as well as the thermostability of the acid.