Article ID Journal Published Year Pages File Type
180144 Electrochemistry Communications 2010 5 Pages PDF
Abstract

The effect of Geobacter sulfurreducens cells was studied on the electrochemical behaviour of 304L stainless steel, emphasizing the role of the soluble electron acceptor (fumarate). In fumarate-lacking media, the presence of G. sulfurreducens induced free potential ennoblement in a few hours. This ennoblement has already been observed in standard media that contained fumarate. Our previous studies have shown that G. sulfurreducens shifted the pitting potential toward the positive values. The pits induced by the presence of the bacteria were wider and deeper than in the absence of bacteria. Here, in fumarate-lacking media, similar shift in pitting potential was observed, but the repassivation phase was strongly improved. AFM analysis showed that pits were identical with those observed in the absence of bacteria at lower potential. In contrast with all the previous work where G. sulfurreducens enhanced corrosion, here at a low concentration of electron acceptor, the presence of the bacteria protected the steel against pitting.

Related Topics
Physical Sciences and Engineering Chemical Engineering Chemical Engineering (General)
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