preparation, identification and performance of cos2/ppy nanocomposite in supercapacitors

Abstract: today, one of the most important concerns of energy researchers is to hybridize the sources of electrical energy production with sources of electrical energy storage and select the type of sources in the desired applications with a view to technical and economic categories [1,2]. in recent years, the use of supercapacitors has been seriously discussed due to the main advantages such as longer life, faster charge and discharge time and much higher power density, very high efficiency, etc. [3]. this study uses a single-step hydrothermal method to synthesize polypyrrole/cobalt disulfide (cos2/ppy) nanocomposites on a ni foam substrate, then the electrochemical behavior of the electrode is tested for use in electrochemical supercapacitors. ni foam has the advantages of high electrical conductivity and surface area (due to its three-dimensional structure), low weight and so on. also in order to compare the efficiency and capacity of the synthesized supercapacitor; cos2 and polypyrrole were synthesized separately on the ni foam. field emission scanning electron microscopy (fesem) was used for the morphology and structural study of the synthesized electrodes. also, x-ray diffraction pattern (xrd), energy dispersive x-ray (edx), and elemental mapping, were used to identify the composition and phase of the produced nanostructures. the electrochemical efficiency of the modified electrodes was investigated in 2 m koh as the electrolyte, by several electrochemical methods such as cyclic voltammetry (cv), galvanostatic charge-discharge (gcd) and electrochemical impedance spectroscopy (eis). cos2/ppy/ni foam electrode prepared in this study, showed high specific capacitance (1441 f g–1 at a current density of 1 a g–1) and excellent cycle stability (94.97% capacity stability after 3000 cycles). also, the maximum energy and power density of this supercapacitor electrode was 35.32 wh kg-1 and 6.30 kw kg-1, respectively.