Evolution of the passive film and organic constituents at the surface of stainless steel immersed in fresh water

• Published in: Journal of colloid and interface science Vol. 318; no. 2; pp. 278 - 289
• Main Authors: Landoulsi, J., Genet, M.J., Richard, C., El Kirat, K., Pulvin, S., Rouxhet, P.G.
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 15.02.2008; Elsevier
• Subjects: AFM; Biofouling; Carbonates - chemistry; Chemistry; Colloidal state and disperse state; Engineering Sciences; Exact sciences and technology; General and physical chemistry; Iron oxides; Membranes, Artificial; Microscopy, Atomic Force; Organic contamination; Oxygen - chemistry; Passive film; Spectrophotometry; Stainless steel; Stainless Steel - chemistry; Surface physical chemistry; Surface Properties; Time Factors; Water - chemistry; X-Rays; XPS; Passive film; Stainless steel; Biofouling; Organic contamination; AFM; XPS; Iron oxides; Water; Atomic force microscopy; Iron oxide; Film; Transition element compounds; X ray; Contamination; Photoelectron spectrometry
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2007.09.087

The evolution of the surface of a conventional stainless steel (AISI 316L) immersed in aqueous medium simulating fresh water (pH ∼8) was studied using XPS and AFM. A detailed analysis of XPS spectra allowed a distinction to be made between oxygen of organic and inorganic nature. During the first 48 h, the main changes concern the inorganic phase: the oxygen concentration in the passive layer increases, owing both to oxidation of metal elements, including conversion of Fe II to Fe III, and to hydration; the molar ratio of oxidized species Fe ox/Cr ox decreases slightly; the formation of colloidal particles, presumably made of ferric hydroxide, is observed by AFM. After longer periods of immersion, the Fe ox/Cr ox is higher, while the coating of colloidal particles reaches a full surface coverage. The amount of organic compounds increases further and the XPS spectra reveal the accumulation of polysaccharides and proteins, which indicate that these organic compounds are of biological origin. XPS and AFM study of stainless steel surface upon immersion in fresh water: formation of colloidal particles presumably made of ferric hydroxide, adsorption of organic compounds of biological origin.