Pervanadyl

Pervanadyl (VO+2) is a pale yellow[1] oxycation of vanadium(V).

It is the predominant vanadium(V) species in acidic solutions with pH between 0 and 2, and its salts are formed by protonation of vanadium(V) oxide in such solutions:[2][3] The ion can form a complex with a single aminopolycarboxylate ligand,[4] or with tridentate Schiff base ligands.

[5] The VO+2/VO2+ redox couple is used at the cathode of the vanadium redox battery.

[6] The standard reduction potential of this couple is +1.00 V.[7]

From left to right: VO + 2 , VO 2+ , V 3+ , and V 2+ in aqueous solution.