The Tuning of Phase, Morphology and Performance of Graphene Oxide/Manganese Oxide for Supercapacitors

抄録

The reduced graphene oxide (rGO)/manganese oxides (MnO₂) composites are obtained from GO/MnO₂ precursor by the microwave-assisted reducing procedures. Characterization indicates that the phase and morphology transformation have been discovered in GO/MnO₂ composite for the first time, and this transition can be explained by a “dissolution-precipitation” model. The capacitive properties of the rGO/MnO₂ electrodes are measured using cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) tests. The rGO/Mn₃O₄ in hydrazine hydrate (H-rGO/Mn₃O₄) exhibits a specific capacitance as high as 324.9 F/g, which is about four times as the GO/MnO₂ precursor (81.25 F/g). It is deduced that the diversity of ionic state of Mn₃O₄, the large specific surface area, and the large reduction degree of GO are favorable to the enhancement of the electrochemical performance. The results show that the H-rGO/Mn₃O₄ nanocomposite from GO/MnO₂ can be used as electrode material for high performance supercapacitors.