Photoelectron spectroscopy of the poly-vanadium transition metal acids

The hydrated compounds H2V12-xMexO31+/-y . n H2O, where Me is Mo (0 less-than-or-equal-to x less-than-or-equal-to 3) and Cr (0.5 <x < 8), were investigated by X-ray photoelectron spectroscopy. The shape and location of the complex core photoelectron lines V 2p, V 3p, O 1s, Mo 3d, Cr 2p and Cr 3p were analysed for the samples with different x values. The valency of the Mo, V and Cr ions, which plays an important role in the electrical conductivity of the compounds, was studied. The temperature-dependent three-stage dehydration of poly-vanadium-molybdenum acid was investigated on the basis of the O 1s core-level photoelectron line.