Electrochromic Properties of the Vanadium Pentoxide Doped with Nickel as an Ionic Storage Layer

The electrochromic property of nickel doped vanadium pentoxide (V2O5) deposited by a co-sputtering system is investigated. The structural analysis of the thin film was done by an X-ray diffraction (XRD) analyzer. The surface morphology of the film was studied by a field emission scanning electron microscopy (FE-SEM). The composition of the film was detected by an Auger analysis. The electrochromic properties of the device were measured by cyclic voltammetry. For the undoped V2O5 thin film, the charge storage capacity increases with the thickness and is 42.58 mC/cm(2) at the thickness of 192.4 nm after 2 h deposition. For the Ni-doped V2O5, the Ni-V-O film shows V2O5 structural dominate with cathode coloration in the lower Ni deposition power region and the charge storage capacity decreases with the increases of the power, while the Ni-V-O film transfers to NiO structural dominate with anodic coloration at the realm of higher Ni doping. The charge storage capacity increases with the increase of Ni doping. It can reach to 101.35 mC/cm(2). The Ni-V-O electrochromic film shows improvement of transmittance difference between colored and bleached values and improvement of charge store capacity as it is compared to pure V2O5 films.