One-pot hydrothermal synthesis of rod-like FeOOH/reduced graphene oxide composites for supercapacitor

FeOOH/reduced graphene oxide (rGO) composites have been synthesized by a facile hydrothermal method. The morphology and structure of the obtained products were examined by scanning electron microscope, Raman, X-ray diffraction, thermo gravimetric analysis, and BET. The results show that the FeOOH nanorods were formed on graphene sheets by oxidation of graphene oxide rather than the O-2 in air, and CH3COONa benefited the growth of FeOOH rods but is not necessary. The products were about 150 nm long obtained with the existence of CH3COONa, while 50 nm long without CH3COONa. The FeOOH/rGO generated with CH3COONa showed capacitance of 501.71 F/g at current density of 2 A/g in 1 mol/L NaOH, while that generated without CH3COONa showed higher specific capacitance of 537.14 F/g. The difference may be related to the amount of rGO, for the former one contained 82.61 wt% FeOOH while the later one contained 66.13 wt% FeOOH, which indicates the quantity of rGO and the their combination played an important role in the performance of the electrode materials.