The effect of 2D-MoS2 doped polypyrrole coatings on brass corrosion.

Conductive polymers have an important potential against the corrosion applications because they are highly resistant to chemicals besides they have homogeneous coating properties and transport metals to more noble regions. However, the major disadvantage of conductive polymers such as polypyrrole (PPy) is their low mechanical strength. In this study, the doping effect of MoS 2 into the PPy coatings by the electropolymerization of polypyrrole (PPy) and exfoliated MoS 2 on the corrosion of brass was investigated. The corrosion protection of these coatings were determined by measuring the corrosion rates with Tafel polarization method in 0.1 M H 2 SO 4 media. PPy and MoS 2 doped PPy (MoS 2 @PPy) coatings were successfully obtained by the use of chronoamperometry technique in 0.2 M H 2 C 2 O 4 solutions with 0.2 M pyrrole and various concentrations of MoS 2. It was observed that MoS 2 @PPy coatings were homogeneously coated without and with all MoS 2 concentrations on the metal surface and well adhered to the brass surface, but MoS 2 @PPy coating with 25 ppm MoS 2 showed the best corrosion protection. The surface and chemical characterizations of the coatings were performed by SEM-EDS. • MoS2@PPy coatings were homogeneously coated on the metal surface and well adhered to the brass surface. • PPy coating has been reducing the corrosion current of brass in sulfuric acid. • MoS2@PPy coating with 25 ppm MoS2 showed the best corrosion protection. • Corrosion parameters obtained by Tafel polarization curves. [ABSTRACT FROM AUTHOR]