title: Effect of protein adsorption on the corrosion behavior of 70Cu-30Ni alloy in artificial seawater.
abstract: Copper alloys often used in cooling circuits of industrial plants can be affected by biocorrosion induced by biofilm formation. The objective of this work was to study the influence of protein adsorption, which is the first step in biofilm formation, on the electrochemical behavior of 70Cu-30Ni (wt.%) alloy in static artificial seawater and on the chemical composition of oxide layers. For that purpose, electrochemical measurements performed after 1h of immersion were combined to surface analyses. A model is proposed to analyze impedance data. In the presence of bovine serum albumin (BSA, model protein), the anodic charge transfer resistance deduced from EIS data at Ecorr is slightly higher, corresponding to lower corrosion current. Without BSA, two oxidized layers are shown by XPS and ToF-SIMS: an outer layer mainly composed of copper oxide (Cu2O redeposited layer) and an inner layer mainly composed of oxidized nickel, with a global thickness of ~30nm. The presence of BSA leads to a mixed oxide layer (CuO, Cu2O, Ni(OH)2) with a lower thickness (~10nm). Thus, the protein induces a decrease of the dissolution rate at Ecorr and hence a decrease of the amount of redeposited Cu2O and of the oxide layer thickness.
authors.affiliation: Laboratoire de Physico-Chimie des Surfaces, UMR 7045 CNRS-ENSCP, Chimie ParisTech, 11 rue Pierre et Marie Curie, F-75005 Paris, France. Electronic address: blanca-torres@chimie-paristech.fr.
authors.forename: Blanca E
authors.initials: BE
authors.lastname: Torres Bautista
authors.affiliation: RSE SpA, Ricerca sul Sistema Energetico, Dipartimento Ambiente e Sviluppo Sostenibile, Via Rubattino 54, 20134 Milano, Italy. Electronic address: MariaLeonor.Carvalho@rse-web.it.
authors.forename: Maria L
authors.initials: ML
authors.lastname: Carvalho
authors.affiliation: Laboratoire de Physico-Chimie des Surfaces, UMR 7045 CNRS-ENSCP, Chimie ParisTech, 11 rue Pierre et Marie Curie, F-75005 Paris, France. Electronic address: antoine-seyeux@chimie-paristech.fr.
authors.forename: Antoine
authors.initials: A
authors.lastname: Seyeux
authors.affiliation: Laboratoire de Physico-Chimie des Surfaces, UMR 7045 CNRS-ENSCP, Chimie ParisTech, 11 rue Pierre et Marie Curie, F-75005 Paris, France. Electronic address: sandrine-zanna@chimie-paristech.fr.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Zanna
authors.affiliation: RSE SpA, Ricerca sul Sistema Energetico, Dipartimento Ambiente e Sviluppo Sostenibile, Via Rubattino 54, 20134 Milano, Italy. Electronic address: Pierangela.Cristiani@rse-web.it.
authors.forename: Pierangela
authors.initials: P
authors.lastname: Cristiani
authors.affiliation: Laboratoire Interfaces et Systèmes Électrochimiques, UPR 15 CNRS, Université Pierre et Marie Curie, 4 place Jussieu, F-75252 Paris Cedex 05, France. Electronic address: bernard.tribollet@upmc.fr.
authors.forename: Bernard
authors.initials: B
authors.lastname: Tribollet
authors.affiliation: Laboratoire de Physico-Chimie des Surfaces, UMR 7045 CNRS-ENSCP, Chimie ParisTech, 11 rue Pierre et Marie Curie, F-75005 Paris, France. Electronic address: philippe-marcus@chimie-paristech.fr.
authors.forename: Philippe
authors.initials: P
authors.lastname: Marcus
authors.affiliation: Laboratoire de Physico-Chimie des Surfaces, UMR 7045 CNRS-ENSCP, Chimie ParisTech, 11 rue Pierre et Marie Curie, F-75005 Paris, France; Laboratoire Interfaces et Systèmes Électrochimiques, UPR 15 CNRS, Université Pierre et Marie Curie, 4 place Jussieu, F-75252 Paris Cedex 05, France. Electronic address: isabelle.frateur@upmc.fr.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Frateur
mesh_terms: D000327:Adsorption; D000818:Animals; D002417:Cattle; D003300:Copper / Q000737:chemistry*; D003343:Corrosion; D017097:Electric Impedance; D055664:Electrochemical Techniques; D009532:Nickel / Q000737:chemistry*; D010084:Oxidation-Reduction; D012623:Seawater / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000302:isolation & purification*; D013499:Surface Properties
chemical_list: C062136:nickel copper alloy; D012710:Serum Albumin, Bovine; D003300:Copper; D009532:Nickel; C000520:cuprous oxide
keywords: Copper alloy; EIS; Protein adsorption; Seawater; Surface analysis