RT info:eu-repo/semantics/article
T1 In situ monitoring of pit nucleation and growth at iron passive oxide layer using combined atomic force and scanning electrochemical microscopy
A1 Souto, Ricardo Manuel
A1 Izquierdo Pérez, Javier
A1 Eifert, Alexander
A1 Kranz, Christine
K1 localized corrosion
K1 single pit nucleation
K1 iron
K1 combined AFM–SECM
K1 imaging
AB Generation of single corrosion pits and in situ monitoring of pit growth on iron exposed to 0.5 M NaCl solution was achieved using combined atomic force - scanning electrochemical microscopy (AFM-SECM). Pits as small as 2.7 μm in diameter were formed at arbitrary locations on the substrate by local generation of highly concentrated nitric acid in the vicinity of the AFM-SECM probe. Addition of nitrite ions to the environment, which act as corrosion inhibitors for iron, ensures passivation of the metal, and hinders metal corrosion despite exposure to the chloride-containing media. Localized acidification was achieved by oxidizing nitrite ions at the probe. Acidification in combination with the high chloride content in the solution leads to a local rapid attack at the surface and pit generation below the AFM-SECM probe. Besides improved spatial resolution and precise control of the pit nucleation site, combined AFM-SECM allows simultaneous imaging of the generated pits by the AFM tip.
YR 2015
FD 2015
LK http://riull.ull.es/xmlui/handle/915/19071
UL http://riull.ull.es/xmlui/handle/915/19071
LA en
DS Repositorio institucional de la Universidad de La Laguna
RD 24-may-2024