PhD defense Julie Dutems"Thin passive film characterization by surface plasmon resonance (COUPLES)"

"Thin passive film characterization by surface plasmon resonance (COUPLES)"

Abstract:

Metals such as aluminum and its alloys are commonly used in industries and high technology domains, where their exposition to severe environments lead them to corrode. Some of them have a defense mechanism involving the formation of a passive film, a protective complex oxide layer just a few nanometer thick, that limits this degradation.
The passive film characteristics, incl. thickness, complexity and resistivity against corrosion in different environments, are typically studied using electrochemical methods. However, their extremely thin thickness and evolution tend to limit the process, and complementary measurements are necessary to validate the electrochemical models. The main goal of this thesis is to establish an optical method, known as surface plasmon resonance, in order to help characterize passive films in situ during their electrochemical characterization. The research successfully demonstrated the feasibility of using surface plasmon resonance to detect aluminum passive films, composed of alumina, throughout their electrochemical characterization process. The thicknesses extracted from the electrochemical characterization were correlated with those obtained through optical means. Additionally, the plasmonic system utilized was calibrated using alumina layers with known thicknesses, enabling the retrieval of naturally existing passive film thicknesses exclusively through surface plasmon resonance. This research highlights the potential of surface plasmon resonance as a valuable tool for unique characterization of passive films, in particular during electrochemical characterization.

Jury:

• Yves Jourlin, Hubert Curien Lab, Supervisor
• Nicolas Crespo-Monteiro, Hubert Curien Lab, Advisor
• Geneviève Chadeyron, ICCF, Univ. Clermont Auvergne, Examiner
• Florence Garrelie, Hubert Curien Lab, Examiner
• Nicolas Mary, MatéIS, INSA Lyon, Examiner
• Aurélien Bruyant, Univ. de Technologie de Troyes, Reviewer
• Francis Vocanson, Hubert Curien Lab, Reviewer
• Myriam Zerrad, Institut Fresnel, Reviewer
• Christophe Heau, HEF IREIS, Invited