Vanadium dioxide (VO2) and divanadium pentoxide (V2O5) nanostructures have been synthesized by a thermal evaporation method. The growth follows vapor-solid (VS) growth mechanism. The electrical properties of VO2 nanowires and V2O5 nanowires and the cathodoluminescence (CL) of V2O5 nanowires were investigated.
In the synthesis of stick-like VO2 nanostructures, argon was used as the carrier gas. Varying the growth temperatures can lead to different morphologies. The sizes of these structures are 100 nm - 5 □m in diameters and 3-10 □m in lengths.
For V2O5 nanowires, the reaction proceeded under argon and oxygen atmospheres. The nanowires were grown on silicon, ITO-coated glass, and glass as the substrates. The growth temperature and heating time of ITO-coated glass substrate and glass substrate were different from the V2O5 nanowires on silicon substrate. The growth temperature of ITO-coated glass and glass substrate are lower than the silicon substrate. Prolonging the annealing time was found to play a role to decrease the defects in the V2O5 nanowires. The diameters and lengths of nanowires are 50-100 nm and 3-10 □m in lengths, respectively.
Electrical properties of stick-like VO2 nanowire and V2O5 nanowire were measured. The resistivities of VO2 and V2O5 are 16.5 Ω-cm and 2.21 Ω-cm, respectively. The CL spectrum of V2O5 nanowires exhibits a green light emission peak at 550 nm corresponding to an energy gap of 2.3 eV.

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