The time dependence of the d. c. conductivity and the current-voltage characteristics of vanadium pentoxide xerogel films of thicknesses ranging between 5 and 1,000 nm have revealed that the conduction in this system is purely electronic. From 1/f-noise measurements an upper limit of 10**1**7 to 6 multiplied by 10**1**8 cm** minus **3 for the charge carrier concentration could be estimated which showed weak thickness dependence. These figures are approx. two orders of magnitude higher than those of single crystal V//2O//5, and also two orders of magnitude lower than the V**4 ** plus concentration in either the films or the single crystals. This suggests that the higher conductivity of xerogels is associated with film hydration which increases the number of V**4** plus sites active in the conduction process.
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