Modified TiO₂coatings for cathodic protection applications

Abstract

A bilayered electrode bearing the configuration SnO 2 jTiO 2 over a substrate like transparent conducting Indium Tin Oxide coated glass was found to store the charge accumulated during ultraviolet illumination. Photogenerated electrons from TiO 2 are transferred to SnO 2 that store the excess charge via cation intercalation. A red shift in the absorbance of the coating was observed due to the reduction of the valence state of Sn during charging and a high capacitance in the bilayer electrode was detected by ac impedance measurements. The charge storage property of SnO 2 jTiO 2 electrode makes it a candidate material to be used as an anode for improved photocathodic protection of metals and/or steels.

Polymers as Corrosion Inhibitors for Metals in Different Media - A Review

“…Among the several methods of corrosion control such as cathodic protection [1,2], anodic protection [3], coating [4] and alloying, the use of chemical inhibitors is often considered as the most effective and practical method of corrosion prevention. A corrosion inhibitor is a chemical additive which when added to a corrosive aqueous environment reduces the rate of metal wastage.…”

Fabrication of CdTe/ZnS core/shell quantum dots sensitized TiO2 nanotube films for photocathodic protection of stainless steel

“…A 0.5 M Na 2 SO 4 + 0.5 M HCOOH mixed solution (pH 9.60)was used as the electrolyte [3,31]. The as-prepared film was used as a photoanode with an exposed area of 1 cm 2 and served as the working electrode.…”

“…Cathodic protection is an important approach to metal corrosion controlby means of an applied direct current.The essential principle of photocathodic protection of TiO 2 films is similar to that of cathodic protection [1][2][3][4][5][6].When a TiO 2 film as a photoanode is illuminated under a proper resource of light (as shown in Fig.1), photogenerated electrons can be transferred from the film to the metal coupled with the film, causing the cathodic polarization of the metal. Thus,the potential of the metal is shifted negatively, and its corrosion rate is reduced.Photocathodic protection does not need an externally supplied electric current or sacrificial anodes, so it is an environmentally friendly technique.…”

“…The application of TiO 2 films inthe photocathodic protection of metals has an attractive prospect because it is an environmentally friendly and low costmethod without consumption of electrical energy [1][2][3][4][5][6].However, most of visible light cannot be effectively absorbed by a pure TiO 2 film because of its wide band-gap (E g =3.2 eV).…”

Nano-indentation investigations of the mechanical properties of thin TiO2, WO3 and their composites layers, deposited by spray pyrolysis

“…42 It was also recently shown that the unique optical and electric properties of TiO 2 unveil the possibility for its use also as photo-catalytic anticorrosion protection of steels. [43][44][45][46][47][48][49] Considering the investigation of T. Tsai and co-authors 50 it is expected that deposited on steel, TiO 2 layers will create photocathode protection under the influence of UV irradiation. This protection property is based on the transfer of photo-generated electrons to the metal substrate, as a result of which its electrode potential becomes more electronegative than its corrosion potential.…”