Preparation of CTAB-Assisted Hexagonal Platelet Co(OH)2/Graphene Hybrid Composite as Efficient Supercapacitor Electrode Material

Abstract

In this paper, our work deals with the preparation of cetyl trimethylammonium bromide (CTAB)-assisted hexagonal platelet β Co(OH)2 via a simple hydrothermal process and its graphene-based hybrid composite with improved electrochemical properties. The prepared materials were successfully characterized by FTIR, XRD, FESEM, TEM, and TGA analysis. The materials were subjected to electrochemical analysis by a three electrode system in a 6 M KOH electrolyte in terms of a cyclic voltammetry, cyclic charge–discharge, and electrochemical impedance study. The CTAB-assisted Co(OH)2 with hexagonal architecture exhibited the highest specific capacitance of 312 F/g at a 2 mV/s scan rate and 285 F/g at a 2 A/g constant discharge current density. The high utility of pseudocapacitive Co(OH)2 is achieved only in its graphene-based hybrid composite, which responded with specific capacitance of 532 F/g at a 2A/g current density and a 94% specific capacitance retention over 500 charge discharge cycles.