Symmetric supercapacitor device applications of rGO / Co3O4 / polypyrrole nanocomposites

Abstract

Symmetric supercapacitor electrode design and synthesis of micro-nano structured metal oxide (Co3O4) and polypyrrole with reduced graphene oxide (rGO) have played an important role in supercapacitor investigations. The characterizations of rGO/Co3O4/PPy nanocomposites were given by FTIR-ATR, SEM-EDX, TGA-DTA, BET surface, and porous analysis and Four-point probe analysis. The symmetric rGO/Co3O4/PPy supercapacitor devices were presented in different initial feed ratios of [rGO](o)/[Co3O4](o)/[Py](o) = 1:5:1; 1:5:2; 1:5:5 and 1:5:10 for 2 M and 6 M KOH solutions. The highest specific capacitances, energy and power densities of C-sp = 896 F x g(-1), E = 31.75 Wh x kg(-1) and P = 11,705 W x kg(-1) for [rGO](o)/[Co3O4](o)/[Py](o) = 1:5:10 in 2 M KOH solution and C-sp = 1370 F x g(-1) for [rGO](o)/[Co3O4](o)/[Py](o) = 1:5:5 and E = 31.43 Wh x kg(-1) and P = 11,600 W x kg(-1) for [rGO](o)/[Co3O4](o)/[Py](o) = 1:5:1 in 6 M KOH solution. The lowest capacitance retention was obtained as 3.69% in 2 M KOH solution for [rGO](o)/[Co3O4](o)/[Py](o) = 1:5:1 after 1000 cycle charge/discharge performances by CV method. Symmetric supercapacitor of rGO/Co3O4/PPy should open up new opportunities for the next-generation high-performance supercapacitors.