Photoelectrochemical Properties of Polycrystalline TiO2Thin Film Electrodes on Quartz Substrates

Abstract

Thin film electrodes of TiO2 have been prepared by vapor deposition of Ti on a quartz substrate followed by partial oxidation to leave a thin Ti layer as back‐side contact. The electrodes were characterized for their photoelectrochemical activities both on illumination through the electrolyte and through the substrate (back‐side illumination). The transparent substrate made it possible to record the action spectrum for back‐side illumination down to 250 nm. Simple theory has been used to estimate bandgap, flatband potential, and doping density. Observed bandshifts in the action spectra due to changes in doping density and electrode potential have been shown to be in accordance with theory.

Solar Energy Materials

“…[135] The ratio of the collection efficiency, obtained from the IPCE measurements, for SE and EE illumination is sensitive to the ratio of L n /d, where d is the film thickness of the mesoporous film. This method to determine L n was originally described by Sö dergren et al [135] for DSSCs, adapting the work by Lindquist et al [136] Recently, it has been discussed by Halme et al [137] and by Barnes et al [138] Good DSSCs are generally characterised by L n values that are two to three times the film thickness.…”

Photoelectrochemical behavior of composite metal oxide semiconductor films with a WO3 matrix and occluded Degussa P 25 TiO2 particles

“…5 for the composite film samples were acquired with both front and rear illumination geometries [15][16][17][18]. Comparing the data for the two situations: (a) The IPCE values are higher for rear illumination vis-à-vis illumination through the electrolyte.…”

“…To evaluate this model, we compared data and simulations for both front (electrolyte side) and rear (substrate side) illumination geometry [15][16][17][18], and compared photoaction spectra with their counterparts for composite semiconductor films where the matrix is a metal, such as nickel [1,[19][20][21][22][23][24].…”

Influence of Cr on photoelectrochemical properties of TiO2 thin films

“…The most popular dopant for modification of the photoelectrochemical properties of TiO 2 is Cr 2 O 3 [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33]. Various Cr-TiO 2 materials have been studied including single crystals [18][19][20], polycrystalline [21][22][23][24][25][26], nanocrystalline [27] both chemical vapour deposition (CVD) [28] and physical vapour deposition (PVD) [29] thin films. It is generally assumed that Cr does increase the visible light response and decrease the ultraviolet response.…”