One-Step Electrochemical Synthesis of Polypyrrole-Graphene Nanocomposite Film on the Copper and Its Corrosion Protection Performance

Electropolymerized polymer coatings on copper can replace for the carcinogenic chromate coating [1]. In this work, the corrosion protection ability of electropolymerized polypyrrolegraphene(Ppy-G) nanocomposite coating on has investigated by using the cyclic voltammetry method [2]. The synthesized coatings were characterized by Fourier Transform InfraredSpectroscopy (FT-IR), UV-visible absorption spectrometry and Scanning Electron Microscopy(SEM). The anticorrosion performances of nanocomposite coatings were investigated in 5000 ppm NaCl solution by the potentiodynamic polarization technique and electrochemical impedance spectroscopy (EIS). Corrosion protection is often afforded by isolating the metal from the corrosive environment by using polymer coatings. The current corrosion decreases significantly from 3.3 μAcm-2 for uncoated copper to 0.095 μAcm-2 for Ppy-G nanocompositecoated copper. The corrosion rate of the nanocomposite coated copper is found to be 7.08×10-4mmyear-1, which is ~50 times lower than that observed for bare copper. The potential corrosionincreases from -0.84 V versus Ag/AgCl for uncoated copper to -0.78V versus Ag/AgCl for nanocomposite coated copper electrode. The positive shift (anodic protection) of ~0.06V in potential corrosion indicates the protection of the copper surface by the Ppy-G nanocomposite coatings. The EIS results are in good agreement with the potentiodynamic polarizationmeasurements. This study demonstrates that Ppy-G nanocomposite has excellent corrosion protection properties and can be consider a potential coating material for the corrosion protection of copper in aqueous 5000 ppm NaCl.

کلیدواژه ها:

Copper ، Polypyrrole-graphene ، Electrochemical Synthesis ، Corrosion