Hierarchical carbon@Ni₃S₂@MoS₂ double core-shell nanorods for high-performance supercapacitors

Hierarchical carbon@Ni₃S₂@MoS₂ (C@Ni₃S₂@MoS₂) double core-shell nanorods have been synthesized by a facile hydrothermal method using highly conductive carbon/Ni (C/Ni) nanorods as both the precursor and template. As supercapacitor electrodes, the C@Ni₃S₂@MoS₂ nanorods deliver a specific capacitance as high as 1544 F g^-1 at a current density of 2 A g^-1 with excellent cycling stability (retaining 92.8% of the capacitance after 2000 cycles at a current density of 20 A g^-1). The C/Ni nanorods as the backbone played crucial roles in enhancing the rate performance of the device, in the meanwhile, interconnected MoS₂ nanosheets on the shell provided numerous accessible surfaces and contacts with the electrolyte. Our work demonstrated an effective design of robust hierarchical double core/shell nanostructures, which could provide a general and promising approach to fabricate high-performance materials for energy storage applications.