Naslov
Chromium Passivity in Sulfuric Acid Solution

Autori
Lajci, Nushe ; Petrović, Željka ; Metikoš-Huković, Mirjana

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstract of the 8th Spring Meeting of the International Society of Electrochemistry Advances in Corrosion Science for Lifetime Prediction and Sustainability / - Lausanne, 2010, P-018

Skup
8th Spring Meeting of the International Society of Electrochemistry Advances in Corrosion Science for Lifetime Prediction and Sustainability

Mjesto i datum
Columbus (OH), Sjedinjene Američke Države, 02.05.2010. - 05.05.2010

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Chromium; Passive film; Semiconducting properties; Point defect model

Sažetak
Passivity of chromium in 0.5 M sulfuric acid has been explored using cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy. The results of potentiostatic measurements have shown that the passive current density is potential-independent, while the thickness of the passive layer increases linearly on the applied potential, which is consistent with the postulation of the Point Defect Model. The Mott-Schottky analysis revealed that the passive film is an n-type semiconductor (related to the outer Cr(OH)3 layer). No evidence for p-type behavior was obtained, indicating that the cation vacancies do not have a significant population density in the film compared with the two donors (cation interstitial and oxygen vacancies). The transpassive state comprise a thick, porous oxide film on the surface, with characteristics consistent with the oxidative ejection of Cr(VI) species from the barrier layer.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA