Enhanced Symmetric Supercapacitive Performance of Co(OH)2 Nanorods Decorated Conducting Porous Graphene Foam Electrodes

•Hierarchical entangled Co(OH)2 nanorods (NRs) anchored on graphene foam (GF) and stainless steel (SS) electrodes by a facile chemical bath deposition method.•The electrochemical capacitive performance of Co(OH)2/GF and Co(OH)2/SS electrodes is investigated and maximum capacitance about 1139 F g−1 is found for Co(OH)2/GF electrode.•The higher energy density and capacitance are found for Co(OH)2/GF electrode based symmetric supercapacitor than ever reported for Co(OH)2/SS electrodes.

Hierarchical entangled Co(OH)2 nanorods (NRs) are anchored on graphene foam (GF) electrodes by using a facile chemical bath deposition (CBD) method. The porous, conducting, and higher specific area access offered by the interconnected 3D graphene framework along with unique Co(OH)2 NRs morphology of electrode displays ultrahigh specific capacitance, energy and power density. The Co(OH)2/GF electrode reveals maximum specific capacitance about 1139 F g−1 at 10 A g−1 charge-discharge current density in 1 M KOH aqueous solution. Moreover, Co(OH)2/GF electrode in the symmetric supercapacitor device, reveals a high energy (13.9 Wh kg−1) with power (18 kW kg−1) density. These results promote the potential applicability of Co(OH)2/GF electrode in the supercapacitor field with effective boosting in charge transfer and storage mechanism.