Molybdenum-vanadium mixed oxides synthesized by the hydrothermal method

摘要

The effect of pressure (5-20 MPa) on the process of hydrothermal synthesis of a molybdenum-vanadium mixed oxide from a molybdenum-vanadium mixed poly(oxyacid) is studied. It is shown that the synthesis product is a solid solution of isomorphically substituted vanadium pentoxide with a pressure-independent composition. With increasing pressure, the degree of crystallinity of the synthesized products increases, concentration of isolated V(IV) ions decreases, habitus of the crystals changes from prismatic to needlelike, and overall dispersity increases. This makes it possible to regard the pressure as a dispersing factor for the synthesis of nanostructured molybdenum-vanadium oxides.