Mott‐Schottky Plots and Flatband Potentials for Single Crystal Rutile Electrodes

Abstract

Ideal Mott‐Schottky plots were obtained for TiO2 single crystal electrodes after a special surface preparation procedure. Precise flatband potentials were determined as a function of pH for three different types of TiO2 boules; significant differences between boules were observed. These differences were reflected in corresponding differences in the electrode potential for the onset of anodic photocurrent. Surface treatments that produced linear Mott‐Schottky plots but with frequency dispersion results in apparent flatband potentials that did not correlate with the potential for the onset of anodic photocurrent. Ideal Mott‐Schottky behavior could only be obtained for the specially prepared crystals if the electrolyte concentration was greater than 0.25M.

Physicochemical Characterization of Passive Films and Corrosion Layers by Differential Admittance and Photocurrent Spectroscopy

“…However, we have to mention that, although the validity of Eq. (8) has been tested rigorously for several SC/El interfaces, [43][44][45][46][47][48][49][50] since the seminal work of Dewald 36 on single crystal ZnO electrodes, in many cases a misuse has been made of such equation.…”

Aging of Single‐Crystal TiO2 Rutile Electrodes

“…(3) reported that in order to minimize frequency dispersion in MS plots the electrolyte concentration had to be kept above 0.25M. (3) reported that in order to minimize frequency dispersion in MS plots the electrolyte concentration had to be kept above 0.25M.…”

“…Photocathodes on the basis of p-InP became an interesting model system for hydrogen evolution when Heller and co-workers first demonstrated a solar-to-chemical energy conversion efficiency of 13% (1)(2)(3)(4). In their work, finely dispersed Rh as electrocatalyst for hydrogen evolution was deposited on the electrode surface.…”

Pitting susceptibility of induction-quenched pipeline with microstructural heterogeneity

“…The donors result mainly from oxygen vacancies. A higher donor density represents that the structure of passive film is more defective [30]. The presence of chloride in the test solution can alter the film structure, as shown by the Mott-Schottky plots in Fig.…”

“…where e is the dielectric constant of the semiconductor (&40 for the passive film of iron [30]), e 0 is the vacuum permittivity (=8.854 9 10 -10 F/m), e is the electron charge (-1.6 9 10 -19 C), N D is the donor density; E is the applied potential; E fb is the flat-band potential, k is the Boltzmann constant (1.38 9 10 -23 J/K), and T is the absolute temperature. By using Eq.…”