Area Effects on the Mott-Schottky Behavior of Anodic Films Formed on AISI304 Stainless Steel

摘要

Porous oxide layers formed on AISI 304L stainless steels by hot acid anodic treatments had both n-type and p-type semiconductive behavior as in the case of compact films. The charge carrier density increase after anodizing was mainly related to the film porosity. An additional effect on the acceptor concentrations was observed due to molybdate and niobil oxalate incorporation. The results showed that the Mott-Schottky approach should consider the influence of the active surface area to estimate the dopant concentrations of oxide films formed by anodization on stainless steels. The estimation of the electronic parameters of the film disregarding the area effects may produce inconsistent results.