Electrochemical synthesis of polypyrrole films on copper from phytic solution for corrosion protection

• A “green” reagent, phytic acid (IP6), was doped in polypyrrole (PPy) on copper.
• The PPy-IP6 layer induces a passive state on copper.
• The PPy-IP6 coating shows excellent protection against corrosion in NaCl solution.

Phytic acid (C6H18O24P6), the principal phosphorous storage form in many plant tissues, is a green material. A polypyrrole (PPy) doped with phytic acid (IP6) was electrosynthesised on copper from an aqueous phytic acid solution. Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and SEM were used to characterise the polymer. The polymer-covered copper was subjected to a corrosion test in NaCl solution. The dissolution of copper covered with PPy-IP6 was found to be greatly inhibited in NaCl solution. The inhibition indicated protection of the PPy-IP6 layer against copper corrosion.