TiO₂ Thin Film Electrodes: Correlation between Photocatalytic Activity and Electrochemical Properties

Abstract

The results of Mott-Schottky measurements on thin film TiO 2 electrodes have been compared with the photocatalytic activities of these films for the photocatalytic reduction of methylviologen and the oxidation of methylene blue, respectively, under UV light irradiation. The purpose of this study was to find an alternative method to predict the photocatalytic activity of titanium dioxide thin films. While impedance measurements were carried out on FTO-glass, the activity tests were performed separately on standard glass substrates. The initial photonic efficiency of the reduction of methylviologen was found to correlate with both the flatband potential and the donor density of the investigated titanium dioxide thin film electrodes. The more negative the flatband potential the higher are both the donor density and the photonic efficiency of the photocatalytic methylviologen reduction. No such dependency was found, however, for the photonic efficiency of the methylene blue oxidation.

Surface characterization, electrochemical properties and in vitro testing of hierarchically structured titanium surfaces

“…For the blasted sample CB, the Mott-Schottky plot is linear in a large potential region, from 0 to 0.7 V. However, at potentials close to the flatband potential the curve shows non-linear behavior. This is typically found for passive films where the semiconducting innermost layer is covered by a more resistive outer layer [41][42][43][44][45]. For samples AT-II and AT-I the Mott-Schottky plots are non-linear in the entire potential region.…”

Electronic properties of anodized TiO2 electrodes and the effect on in vitro response

“…It has been argued that for insulating films the sharp decrease of the C −2 versus E curve close to the flat band potential is due to the capacitance of the oxide . However, for the thin films investigated in the present study it seems more plausible that the nonlinear part is due to changes in the oxide properties as described for other similar system …”

Impact of Ti‐V ratio on the crystalline phase/visible light activity of TiV‐oxide photocatalyst

“…The values are given in Table 1 and are identical to the earlier report [22]. However, it may be noted that photonic efficiency is dependent on the type and design of the reactor as well.…”