Anodic polarisation of a vanadium electrode has been studied in H3PO4 solutions and some phosphate solutions: LiH2PO4, NaH2PO4, KH2PO4 and NH4H2PO4. The anodic behaviour of a vanadium electrode showed similarities in weak concentrated H3PO4, in LiH2PO4 and NaH2PO4 solutions: the polarisation curve exhibited a current peak followed by current oscillations and then a current plateau. Concentrated H3PO4, 1 M KH2PO4 and NH4H2PO4 solutions involved vanadium passivation with a very slight current density plateau. Yellow compound identified to VOPO4.2H(2)O was obtained after controlled potential oxidation of vanadium in 5-10 M H3PO4. Green products were obtained in 1 M phosphate solutions and in 1-3 M H3PO4 on vanadium anode after controlled potential electrolysis. All these vanadophosphate compounds contained the monovalent cation which was present in the solution. (c) 2005 Elsevier Ltd. All rights reserved.