Improved electrochemical behavior of metal oxides-based nanocomposites for supercapacitor

This paper investigates the synthesis and enhanced electrochemical behaviors of ZnO and NiO/ZnO nanocomposites for electrode material of supercapacitors. ZnO and NiO/ZnO nanocomposites were produced via sol-gel technique. Transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM) were used to determine the size and structure of as-synthesized nanomaterials, respectively. The capacitive behavior and charge-discharge characteristics of the electrode using ZnO and NiO/ZnO nanocomposites (as active material) were individually probed with the help of cyclic voltammetry (CV) and galvanostatic charge-discharge tests, respectively. The specific capacitance of nanocomposites-based electrode calculated from galvanostatic charge-discharge tests was 469 F g(-1) at the scan rate of 1 mA g(-1) in 1M Na2SO4 electrolyte. The power density and energy density at the current density of 1 mA g(-1) were determined as 1458.33 W kg(-1) and 91.14 Wh kg(-1), respectively. Hence, NiO/ZnO nanocomposites could be reckoned to be a promising electrode material for supercapacitor while comparing to ZnO-based electrode material.