University of Pretoria,
Keywords: cobalt hydroxide carbonate, graphene, composite, hybrid capacitor, iron-carbonized polyaniline, energy density
Summary:Cobalt hydroxide carbonate has a good electrochemical capability coupled with its, environmentally friendly nature and low cost which makes it a potential high performance material for electrochemical applications when combined with graphene foam (GF) as nanostructured composites. In this report, cobalt hydroxide carbonate/graphene foam (GF) with different mass contents of GF was synthesized by hydrothermal method. An asymmetric supercapacitor device was designed using the highest performance cobalt hydroxide carbonate/ GF composites as a positive electrode and carbonized conductive polyaniline grafted with Iron (C-FP) as the negative electrode. The hybrid device exhibited a high specific capacity of about 69 mA h g-1 with the maximum energy density of 28 Wh kg-1 and power density of 554 W kg-1 at a current density of 0.5 A g-1 in the operation voltage range of 0-1.5 V. These impressive results enable the possible adoption of such cobalt hydroxide carbonate/GF//C-FP devices in high performance energy storage application units.