On the synthesis of monovalent, divalent and trivalent element vanadates

A chimie douce method has been used to prepare vanadates (V 5+ ) of various elements, trivalent (Al, Cr, Fe, In, Y, Bi), divalent (Co, Ni), monovalent (Li, Tl), and a combination of nickel and lithium. By varying several parameters, especially the pH during the synthesis, several types of vanadates have been obtained ranging from orthovanadates (VO 4 3– ) to decavanadates (V 10 O 28 6– ). The pH conditions required to prepare the various vanadates fall nicely within the expectations of the previously reported cation charge-pH diagram.