Electrochemical synthesis of poly(3,4-ethylenedioxythiophene) on stainless steel and its corrosion inhibition performance

Poly(3,4-ethylenedioxythiophene) (PEDOT) coatings have been electrochemically prepared on stainless steel (SS) in acetonitrile and aqueous media, respectively, by the cyclic voltammetry technique. The corrosion behavior of the coated SS was evaluated in 3.5 wt% NaCl solution using anodic polarization and electrochemical impedance spectroscopy, which demonstrate that the polymer coatings are able to mitigate the corrosion of the SS substrate in chloride solution. PEDOT works as the electron exchange medium to passivate the SS underneath and reduce the oxygen on the surface. By comparing the performances, it was clear that PEDOT electrodeposited from an aqueous solution can afford better corrosion inhibition capability.