A facile synthesis of self-assembling reduced graphene oxide/cobalt carbonate hydroxide papers for high-performance supercapacitor applications

Electrode materials as an important component for the supercapacitors (SC) mainly undertake energy storage. Hence, the research hotspots in the SC fields are focused on the active materials of the electrode. In this study, we have provided a facile synthesis method to prepare reduced graphene oxide (RGO) and cobalt carbonate hydroxide (Co(CO₃)_0.5(OH)_0.11·H₂O) nanorod composites. The RGO films were obtained by vacuum filtration of GO papers and hydrothermal method. And during this hydrothermal, Co(CO₃)_0.5(OH)_0.11·H₂O nanorods also grow on the surface of RGO films. The as-fabricated RGO/Co(CO₃)_0.5(OH)_0.11·H₂O composites are characterized by SEM, EDS, XRD measurement. According to the electrochemical research results, the RGO/Co(CO₃)_0.5(OH)_0.11·H₂O electrodes own an ultrahigh volumetric capacitance of 1627 F cm⁻³ at a current density of 0.5 A g⁻¹. Besides, the energy density of the symmetrical supercapacitor (SSc) assembled with the RGO/Co(CO₃)_0.5(OH)_0.11·H₂O electrode material is 9.22 mW h cm⁻³, and the capacity can be maintained 100.0% after 10,000 cycles when the composite material at the current density of 1 A g⁻¹, these promote an efficient electrode material for electrochemical supercapacitor applications.