Room-temperature photoluminescence behavior of α-V2O5 and mixed α-β phase V2O5 films grown by electrodeposition

Vanadium pentoxide (V2O5) films with micro-nanostructure were fabricated by an electrodeposition method using an aqueous solution of NH4VO3. The surface morphology and structural properties of the V2O5 were investigated by SEM and XRD measurements. The results show that the annealing temperature strongly affects the surface morphology, crystal structure, and photoluminescence (PL) properties. The formation of alpha-V2O5 structure occurred when the sample was annealed at temperatures below 500 degrees C. As the annealing temperature increases, some of the alpha-V2O5 structures were distorted and restructured to form a high-quality mix of alpha-beta phase V2O5. This leads to great enhancement of the PL due to the presence of numerous defects on the surface of the V2O5 films. Moreover, the mixing of the alpha-beta phase V2O5 leads to wide absorption and enhancement of the visible-light emission from V2O5 micro-nanostructure.