Controlled synthesis and comparison of NiCo2S4/graphene/2D TMD ternary nanocomposites for high-performance supercapacitors

Abstract

Novel ternary electrode materials based on graphene, NiCo₂S₄, and transition metal dichalcogenides (TMDs) were designed and fabricated with the intention of exploiting synergistic effects conducive to supercapacitive energy storage. Compared to NiCo₂S₄-g-MoSe₂, the NiCo₂S₄-g-MoS₂ electrode exhibited higher specific capacitance, enhanced rate capability (1002 F g⁻¹ even at 5 A g⁻¹, 6.01 F cm⁻² at a current density of 25 mA cm⁻²) and cycling stability (94.8% retention of its original capacity after cycling 4000 times). The mechanism was proposed and this pioneering work will be helpful in making judicious choices of which 2D materials to be selected for supercapacitor applications in the future.