Investigations about the energetics and the electrical properties of niobium thin film, electrochemically grown,
were performed in an organic solution of acetonitrile and lithium perchlorate. The study of the energetics of the
Nb O /organic solution interface was performed by means of a non-destructive optical technique, photocurrent
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spectroscopy. By means of this technique, it was possible estimating the value of the flat band potential and
locating conduction and valence band. A more cathodic value of flat band potential in respect with acidic
solution was found in organic medium. From impedance spectra, the electrical circuit that gives best fitting
values is constituted by two resistances in parallel with two constant phase elements and in series with the
resistance of the electrolyte. On considering the exponential coefficient, the constant phase elements model
distorted capacitances
