Fabrication of ZnCr2O4/MnO2 composite electrodes by sonication procedure for advanced symmetric supercapacitors

Abstract

In order to develop advanced energy storage devices, it is necessary to manufacture supercapacitor electrode that have both long electrochemical cycle lifetimes and high energy densities. These properties can only be obtained by developing heterostructure pseudo-capacitive materials. The combination of MnO2 nanorods and ZnCr2O4 nanoparticles resulted in a synergistic effect, which increased the electroactive surface area for charge storage. This effect was not observed when each component utilized individually. The material ZnCr2O4 nanoparticles facilitated the MnO2 nanorods. In present study, ZnCr2O4, MnO2 and their composite was fabricated by simple sonication process. These fabricated samples were tested by using different techniques which includes X-ray diffraction (XRD), Raman analysis, Brunauer Emmett Teller (BET) and scanning electron microscopy (SEM). Electrochemical analysis of fabricated materials exhibited an exceptional specific capacitance (Csp = 1175.35 F g−1), energy density (Ed = 15.95 Wh Kg−1) and power density (Pd = 869.4 W kg−1). These materials are anticipated to act as the support for electrochemical energy storage devices that utilize an ideal electrode structure, meticulously select the appropriate transition metal oxide (TMO) and analyse electrochemical characteristics for supercapacitive performance. This study exhibits the remarkable efficiency of the nanostructured ZnCr2O4/MnO2 electrode in supercapacitors with high energy density (Ed).