Deposition of tin oxide, iridium and iridium oxide films by metal-organic chemical vapor deposition for electrochemical wastewater treatment

• Published in: Journal of applied electrochemistry Vol. 40; no. 5; pp. 997 - 1004
• Main Authors: Klamklang, Songsak, Vergnes, Hugues, Senocq, François, Pruksathorn, Kejvalee, Duverneuil, Patrick, Damronglerd, Somsak
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.05.2010; Springer Verlag
• Subjects: Chemical Sciences; Chemical vapor deposition; Chemistry; Chemistry and Materials Science; Deposition; Electrochemistry; Engineering Sciences; Industrial Chemistry/Chemical Engineering; Iridium; Material chemistry; Materials; Original Paper; Oxide coatings; Physical Chemistry; Tin oxides; Wastewater treatment; Thin film coating; Wastewater treatment; MOCVD; Electrochemical oxidation; Specific electrode
• ISSN: 0021-891X; 1572-8838
• DOI: 10.1007/s10800-009-9968-1

In this research, the specific electrodes were prepared by metal-organic chemical vapor deposition (MOCVD) in a hot-wall CVD reactor with the presence of O 2 under reduced pressure. The Ir protective layer was deposited by using (Methylcyclopentadienyl) (1,5-cyclooctadiene) iridium (I), (MeCp)Ir(COD), as precursor. Tetraethyltin (TET) was used as precursor for the deposition of SnO 2 active layer. The optimum condition for Ir film deposition was at 300 °C, 125 of O 2 /(MeCp)Ir(COD) molar ratio and 12 Torr of total pressure. While that of SnO 2 active layer was at 380 °C, 1200 of O 2 /TET molar ratio and 15 Torr of total pressure. The prepared SnO 2 /Ir/Ti electrodes were tested for anodic oxidation of organic pollutant in a simple three-electrode electrochemical reactor using oxalic acid as model solution. The electrochemical experiments indicate that more than 80% of organic pollutant was removed after 2.1 Ah/L of charge has been applied. The kinetic investigation gives a two-step process for organic pollutant degradation, the kinetic was zero-order and first-order with respect to TOC of model solution for high and low TOC concentrations, respectively.