High surface area electrodes are essential for the performance of electrochemical devices for energy storage and water treatment. Carbon-based materials, mostly carbon aerogels and activated carbon, have been the usual choice for supercapacitors and capacitive deionization systems while organic-inorganic composite electrodes, featuring dispersed oxide particles on organic backbone in most cases, are currently getting attention for their distinct electrosorption properties. To expand the materials boundary even further to metallic nanowire arrays, it is necessary to develop a corrosion protection scheme that is compatible with the structural complexity of the electrode. To this end, we investigated electropolymerization route to form conformal polymeric corrosion protection barrier on a high surface area electrode based on copper nanowire array. We started from polyaniline since its electropolymerization process has been applied for smooth copper substrate [1]. Copper foils were heat treated in air to grow an intermediate array of copper oxide nanowires. After reducing copper oxide nanowires to copper nanowires preserving the high surface area [2], various polymer coatings were electrochemically grown on the surface of the copper nanowires [3]. We confirm the corrosion protection performance of the polymer coatings in an acidic environment by cyclic voltammetry and electrochemical impedance spectroscopy. The correlation between electropolymerization parameters and copper nanowire corrosion kinetics is discussed.

[1] Berrin Duran, Metehan C. Turhan, Gözen Bereket, A. Sezai Sarac, Electrochim. Acta, 55, 104 (2009).

[2] Evan C. Brown, Ph.D. thesis, Caltech, 2011.

[3] J. Heinze, Synthetic Met., 41-43, 2805 (1991).