High electrochemical performance of morphologically controlled cobalt oxide for supercapacitor application

Abstract

The black antiferromagnetic oxide of cobalt has been paying much interest for supercapacitor applications owing to its elevated theoretical capacitance, superior electrochemical features, and low cost. In this endeavor, Co3O4 materials were prepared using a PVA-assisted hydrothermal technique followed by a proper calcination process. The XRD, XPS, and FTIR studies signify the formation, phase, oxidation state, and bonding nature of Co3O4 materials. The high concentration of PVA template provides nanorod and nanosheet morphologies. The pseudocapacitive behavior of the Co3O4 materials was explained using cyclic voltammetric, galvanostatic charge/discharge measurements. The cyclic voltammetric curves deliver the specific capacitance of 1022 Fg‐1 at a scan rate of 5 mVs‐1.This material also exhibited the specific capacitance of 954 Fg‐1 at a current density of 1 Ag‐1 from galvanostatic charge /discharge studies. It maintained 88% of the primary capacitance after 2000 cycles at a high scan rate of 100 mVs‐1. From this study, it is confirmed that the Co3O4 material is potentially capable of supercapacitor applications.