Electrochemical and optical characterization of RF-sputtered thin films of vanadium–nickel mixed oxides

Electrochromics for smart windows: thin films of tungsten oxide and nickel oxide, and devices based on these

“…[208][209][210][211] The optical properties of these novel materials will be treated from a device perspective in more detail in section IV. Intercalation of Li + into Ni-oxidecontaining films has been researched several times, [352][353][354][355][356] but it seems that the optical properties are not modulated to any large extent. 357,358 This means that electrochromic Ni oxide films only can be used in devices where the optical modulation depends on proton/electron transport.…”

Surface evolution of Ni–V transparent oxide films upon Li insertion reactions

“…The electromotive force of the as-deposited thin films was found to be 3.5 V vs. Li/Li C immediately after cell assembling. The behaviour of r.f.-sputtered thin films of vanadium-nickel mixed oxides during CV has been investigated already by Lourenco et al 14 In order to reach a better resolution, a CV curve at the 10th cycle has been recorded at a slow scan rate of 1 mV s 1 and is reported in Fig. 1(a).…”

“…We have, in fact, followed the capacity fading and the surface passivation during the first hundreds of charge-discharge cycles by complementing the basic electrochemical techniques with the surface-specific methods of AFM and XPS. This complementary approach was considered to be important in the case presented here, where a new material based on mixed Ni-V oxides was developed in our laboratory that was very promising as an optically passive transparent electrode for ECDs with high charge capacity 14 but is affected by a minor but significant and undesirable passivation effect.…”

Surface analyses of In–V oxide films aged electrochemically by Li insertion reactions

“…The films presented an electrochemically active region between 1 and 4.5 V, one large anodic peak around 3.2 V (2 V only on the first cycle) and two ill-defined cathodic peaks at 2 and 3 V. This CV was quite similar to the one observed in Ni-V mixed oxide thin films. 20 In the first insertion step the electrode retained 20% of the inserted charge and in the subsequent cycles it suffered a smaller and gradual loss of capacity. Denis et al 6 observed a similar behaviour for amorphous In vanadates annealed at low-temperature (InVO 4 + 2.3H 2 O) which showed during the first cycle an irreversible charge retention much larger than 20%.…”