Optical absorption studies on (V2O5)1−x–(MoO3)x thin films

Thin films of (V2O5)1−x–(MoO3)x (0≤x≤1) were prepared by the electron beam evaporation technique in an oxygen partial pressure of 2×10−4 mbar and at a substrate temperature of 423 K. The optical absorption studies in the wavelength range 300–1500 nm suggested the increase of the optical bandgap with increasing x and showed a curvilinear behaviour. The width of the localized states Ee estimated from the slopes of ln α vs hν plots of (V2O5)1−x–(MoO3)x films were in the range 0.42–0.35 eV. The electrical conductivity decreased with the increase of composition x.