Ammonium hexadeca-oxo-heptavanadate microsquares. A new member in the family of the V 7 O 16 mixed-valence nanostructures

This paper presents the new mixed valence heptavanadate (NH 4 ) 2 V 7 O 16 micro squares, a further but carbonless member of the vanadium oxide nanotubes and nanourchins family, where ammonium ions replace the long carbon chain amines.