Hybrid nitrogen-doped graphene-supported MoS2 nanosheets with synergistic effect for high-performance supercapacitor electrodes

Efficient supercapacitor electrodes have been developed from a nitrogen-doped graphene-molybdenum disulfide composite (NG/MoS₂) with varying NG concentrations fabricated on nickel foil electrodes. The successful synthesis of NG and MoS₂ nanosheets was confirmed through Raman spectroscopy, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). At the same time, the morphology was studied using FESEM and TEM. The influence of varying NG concentrations on the electrochemical properties of the MoS₂ nanosheets was investigated. The composite containing 1% NG achieved a maximum specific capacitance of 897.6 F/g at a current density of 1 A g⁻¹, surpassing the electrochemical performance of pristine MoS₂, which had a capacitance of 291.1 F/g under the same conditions. This improvement arises from the synergistic interaction between superior catalytic properties found in the MoS₂ nanosheets and conductivity provided by the addition of NG, which was confirmed through electrochemical impedance spectroscopy (EIS). In conclusion, this work may offer a way to fabricate supercapacitor electrodes with improved specific capacitance and energy density for energy storage.

Graphical Abstract