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

Abstract

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/cm2 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/cm2. 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.

Thermal Annealing Effects of V2O5 Thin Film as an Ionic Storage Layer for Electrochromic Application

“…The CV curve of pure V 2 O 5 thin film without thermal annealing shows a cathodic reduction peak (−1.6 V) attributable to Li + intercalation and an anodic oxidation peak (−0.4 V) that corresponds to Li + extraction [28]. The CV measurement of the unannealed V 2 O 5 thin film had a charge capacity of 54.7 mC/cm 2 , as revealed in our previous work [39]. The voltammogram of 200 • C-annealed V 2 O 5 thin film (black line) shows an oxidation peak at the potential of −0.4 V and a slight reduction peak near the potential of −1 V. As the annealing temperature increased to 300 • C, the oxidation peak became strong, and the peak moved to the potential of 0.4 V; the reduction process showed Li + ions intercalated into the V 2 O 5 film as compared to the 200 • C-annealed sample.…”

“…Table 1 is the summary of the transmittan charge capacity, and coloration efficiency of the V2O5 thin film after vario temperatures. Table 2 shows the photographs of the original, bleached, and c of the V2O5 thin films without and after various thermal annealing tempera value at the 650-nm wavelength of the unannealed V2O5 thin film is 15%, a our previous work [39]. As it was annealed, the transmittance difference incr for the 400 °C-annealed sample due to the grain growth of the film's polycry ture created by the rearrangement of atoms through thermal energy.…”

“…S.F. Cogan et al [39] reported that in response to lithium intercalation, the fundamental optical absorption edge of V 2 O 5 shifts to higher energies by 0.20-0.31 eV as the lithium concentration from Li 0 . 0 V 2 O 5 to Li 0 .…”

How the Environment Encourages the Natural Formation of Hydrated V2O5

“…), biosensors (urea, glucose, gene sequence, methylglyoxal etc.) smart glass windows in satellites, and aerospace vehicles. − The device performance may be reduced due to the degradation or permanent modifications in the V 2 O 5 material in contact with humidity for a long-lifetime. However, the hydrated V 2 O 5 , which has water gradients in its structures, can be a suitable material for the long life application where a humid environment is the working condition.…”

Influence of the rf power and oxygen content on structural, electrical, and optical properties of V2O5 thin films prepared via reactive radio frequency sputtering

“…Vanadium pentoxide thin films are intelligent materials that exhibit significant color changes through electro-, photo-, and thermochromic processes [1][2][3]. The chromism of V 2 O 5 films has attracted considerable research interest as promising materials for applications in optical devices [4] and smart chromic sensors [5].…”