Three-dimensional nanoflower–like hierarchical array of multifunctional copper cobaltate electrode as efficient electrocatalyst for oxygen evolution reaction and energy storage application

The study deals with the hydrothermal growth of a CuCo2O4 hierarchical 3D nanoflower-like array on carbon cloth (CuCo2O4@CC), which is a useful multifunctional electrode. The electrocatalytic oxygen evolution reaction (OER) study of the CuCo2O4@CC electrode shows high durability and good activity in 1 M KOH. As an energy storage electrode, it shows a high specific capacitance of 1438 Fg-1 at 10 mA cm-2 in a 3 M KOH electrolyte. The electrochemical stability of the CuCo2O4@CC electrode was tested for 5000 cycles at 10 mA cm-2, and it showed 98.6% stability. This CuCo2O4@CC electrode produces a capacitance of 10 mA cm-2 at an overpotential of 288 mV for the OER, with a Tafel slope of 64.2 mV dev-1. The electrochemical stability measured at an overpotential of 292 mV for 12 h at 10 mA cm-2 shows good electronic stability in an alkaline medium. The enhanced electrochemical performance of the CuCo2O4@CC electrode may be due to the Cu and Co counterparts in addition to the high surface area. The CuCo2O4@CC electrode is a simple, flexible, and cost-effectivive electrode in both electrocatalytic OER and energy storage applications.