Fabrication of magnetic irregular hexagonal-Fe3O4 sheets/reduced graphene oxide composite for supercapacitors

• HFGC was prepared by a facile colloidal electrostatic assembly process.
• The irregular hexagonal-Fe3O4 sheets was loaded onto rGO sheets.
• The excellent performance of HFGC indicates the potential application for supercapacitor.

The magnetic irregular hexagonal-Fe3O4 sheets/reduced graphene oxide composite (HFGC) was fabricated via colloidal electrostatic assembly process, followed a heat treatment process. The TEM images showed that irregular hexagonal-Fe3O4 sheets generated from Fe(OH)3 colloid particles were loaded onto reduced graphene oxide (rGO) sheets. The ideal rectangular cyclic voltammetry (CV) curves of HFGC in different scan rates indicated the character of double layer capacitance with the excellent capacitive behavior. Tested by the galvanostatic charge–discharge (GCD) experiments in 6 M KOH aqueous electrolyte, HFGC exhibited a specific capacitance of 193 F g−1 at 0.3 A g−1. Furthermore, the cycling stability of HFGC was tested under a density of 0.5 A g−1. The capacitance maintain as 90.4% after 1000 cycles, indicating the desirable cyclic stability.