| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1488411 | Materials Research Bulletin | 2014 | 6 Pages |
•Indium oxide performed novel application under visible light.•Indium oxide by sol–gel method behaved better photoelectrochemical properties.•Electrons were transferred to stainless steel from indium oxide once light on.
This paper reports the photoelectrochemical cathodic protection of 304 stainless steel by In2O3 thin-film under visible-light. The films were fabricated with In2O3 powders, synthesized by both sol–gel (In2O3-sg) and solid-state (In2O3-ss) processes. The photo-induced open circuit potential and the photo-to-current efficiency measurements suggested that In2O3 could be a promising candidate material for photoelectrochemical cathodic protection of metallic alloys under visible light. Moreover, the polarization curve experimental results indicated that In2O3-sg thin-film can mitigate the corrosion potential of 304 stainless steel to much more negative values with a higher photocurrent density than the In2O3-ss film under visible-light illumination. All the results demonstrated that the In2O3-sg thin-film provides a better photoelectrochemical cathodic protection for 304 stainless steel than In2O3-ss thin-film under visible-light illumination. The higher photoelectrochemical efficiency is possibly due to the uniform thin films produced with the smaller particle size of In2O3-sg, which facilitates the transfer of the photo-induced electrons from bulk to the surface and suppresses the charge recombination of the electrons and holes.
Graphical abstractIf the conduction band potential of In2O3 is more negative than the corrosion potential of stainless steel, photo-induced electrons will be transferred from In2O3 to the steel, thus shifting the potential of the steel into a corrosion immunity region and preventing the steel from the corrosion.Figure optionsDownload full-size imageDownload as PowerPoint slide
