Development and characterization of electrodeposited cerium and lanthanum-based coatings on the AISI 304 stainless steel
The aim of the present work is to investigate the corrosion behavior of cerium and lanthanum-coated AISI 304 stainless steel samples. The coatings were obtained by cathodic electrodeposition using cerium nitrate and lanthanum nitrate-based electrolytes. The corrosion behavior was evaluated by electrochemical impedance spectroscopy and potentiodynamic polarization. The oxide layers were examined by confocal laser scanning microscopy and scanning electron microscopy. X-ray photoelectron spectroscopy was employed to assess the surface chemical states. The deposition process was successful. Cerium was found as a mixture of Ce3+ and Ce4+ species. Different electrodeposition conditions were tested, varying the applied potential and treatment time. The results point to an increase of the corrosion resistance of the AISI 304 substrate due to the presence of the cerium-based film. Lanthanum-based films will be developed in the next steps of the project.