Spectroscopic study of VOPO4,2H2O intercalation compounds

The results of spectroscopic studies of vanadyl phosphate dihydrate (VOPO4,2H2O) intercalation compounds are reported. EXAFS experiments carried out on Ca and Cd intercalated VOPO4,2H2O show the inserted cation localized in the vicinity of the vanadium, while the X-ray powder diffraction reveals a decrease of the crystallinity as well as a structural distortion upon intercalation. In the corresponding I.R spectra, VO and PO absorption bands are not greatly modified indicating that no significant structural deformation occurs in the VOPO4 layers. OH stretching and bending modes and thermal analysis give evidence for a change in the hydration rate.