An all chemical route to design a hybrid battery-type supercapacitor based on ZnCo2O4/CdS composite nanostructures

Abstract

Recently, spinel-type binary metal oxides have attracted enormous interest in energy storage devices. In supercapacitors improving energy density is still challenging task and the composite nanostructures are found to address this issue in some extent. Herein, a composite nanostructure based on ZnCo2O4/CdS was synthesized on nickel foam using hydrothermal and successive ionic layer adsorption and reaction (SILAR) methods. A hydrothermally synthesized ZnCo2O4 nanoflowers were coated by CdS nanoparticles by varying SILAR cycles and studied its electrochemical performance. The ZnCo2O4/CdS nanostructured electrode with optimized four SILAR cycles of CdS coating exhibited a high areal capacity, energy density and power density of 2658 mCcm(-2), 517 mu Whcm(-2) and 17.5 mWcm(-2) at 25 mA, which is higher than pristine ZnCo2O4. This work show ZnCo2O4/CdS nanostructure is a favorable electrode for supercapacitors.