Enhanced supercapacitor performance through surface modification: Binder-free electrode synthesis of Ni3S2/MoS2/rGO on Ni-foam with superior cyclability

Tuning of microstructure and composition of the material is highly desirable for enhancing the specific capacity, rate capability and cycle stability of supercapacitor electrode materials. Herein direct growth of surface modified hierarchical Ni3S2/MoS2/rGO hybrid nanomaterial on Ni foam was successfully carried out by a one-step hydrothermal technique. Furthermore, the structural, morphological, elemental composition and electrochemical properties of as synthesized electrode material were analysed. The as synthesized Ni3S2/MoS2/rGO composite electrode delivered a very high specific capacity of 2580 F/g @ 1 A/g and excellent cycling stability with 100 % capacitance retention for 10,000 charge-discharge cycles with specific capacitance of 600 F/g @ current density 20 A/g. In addition, the assembled two electrode symmetric system showed high specific capacity 100.26 F/g @1 A/g and superior energy density of 112.79 Wh/kg with corresponding power density of 2699.82 W/kg @ 1 A/g. The results proved that the Ni3S2/MoS2/rGO directly grown on Ni foam without the addition of any external nickel source and binding polymer is an ideal candidate for supercapacitor applications.