Room Temperature Surface Oxidation by Alkalization of Binder Free CuO Nanostructured Electrode for Enhanced Supercapacitive Performance

Abstract

The copper oxide (CuO) nanostructures are synthesized via facile oxidation of Cu foil in an aqueous KOH solution at room temperature. A precleaned Cu foil immersed in a 0.1 M aqueous KOH solution for different time periods (36–72 h) systematically converts its surface into nanochained to rice husk morphology and then agglomerated dense nanoclusters. The impact of immersion time on the morphology and consequently supercapacitor performance is studied. The CuO nanostructure synthesized at an immersion time of 60 h shows a maximum specific capacitance of 302 Fg–1 at a scan rate of 2 mV s−1. The capacitance retention reaches up to 87% after 2000 cycles.