Electrode materials with outstanding stability and electrochemical activity are ideal for high-performance supercapacitors. Herein, we developed a simple two-step method for fabricating NiCo2S4/EG/Ti3C2Tx nanocomposites with a sheet(2D)-rod(1D)-sheet(2D) structure. The NiCo2S4 rods were embedded into the expanded graphite (EG) sheets via an in-situ hydrothermal method, then the Ti3C2Tx sheets were assembled with NiCo2S4/EG by an electrostatic self-assembly method. The obtained NiCo2S4/EG/Ti3C2Tx nanocomposites exhibited a synergistic effect among the components. The addition of EG inhibited the volumetric effect of NiCo2S4 during charging and discharging processes, while the high conductivity of Ti3C2Tx promoted charges transfer. The rod-like structure of NiCo2S4 effectively inhibited the self-stacking of Ti3C2Tx sheets. Consequently, the optimized composite exhibited an excellent specific capacitance of 1837.9 F·g−1 at a current density of 1 A·g−1. Additionally, the composite electrode exhibited a capacitance retention of 73.5 % during 10,000 charging-discharging cycles at a current density of 20 A·g−1.
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