Copper vanadates were synthesized using co-precipitation method. Scanning electron microscopy showed that the crystallinity of the materials increased with heat treatment temperature. X-ray diffraction study showed the material heat treated at 600 degrees C was stoichiometric triclinic (alpha-CuV2O6, whereas the material heat treated at 400 degrees C was an oxygen deficient counterpart of (alpha-CuV2O6, which was CuV2O5.88 obtained from the thermogravimetric data. X-ray absorption near edge spectroscopy confirmed a valence state of +5 for V in alpha-CuV2O6, whereas a valence state lower than +5 in CuV2O5.88. The symmetrical degree of the [VO6] octahedron in alpha-CuV2O6 is higher than that of orthorhombic V2O5 and oxygen deficiency CuV2O5.88. The Raman band of the V-O-1 stretching vibration showed a red shift for copper vanadates with respect to orthorhombic V2O5 because of the electrostatic attraction between Cu and O-1 atoms. Moreover, the V4+-O-1 I stretching vibration was observed for oxygen deficient CuV2O5.88. (c) 2005 Elsevier B.V. All rights reserved.