VO₂ /V₂ O₅ :Ag Nanostructures on a DVD as Photoelectrochemical Sensors

The electrochemical deposition of a mixed oxide on the Ag nanostructured surface of a commercial digital versatile disc (DVD) is described. The VO₂ /V₂ O₅ mixture shows interesting photoelectrocatalytic performances under visible-light illumination after diffusion of the Ag⁺ ions from the Ag-DVD substrate through the layer and formation of surface vanadates, which also allows it to be applied as an inexpensive sensing device. The samples were characterized with X-ray photoemission spectroscopy (XPS), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), and Raman measurements. The sensing properties towards oxidizable organic substances, such as glucose, were tested.