A novel (alpha-beta)NiS/Ni3S4-rGO electrode material for supercapacitors

A novel electrode material of alpha-NiS, beta-NiS and Ni3S4 particles co-decorated rGO is obtained by co-reduction of Ni2+ and GO with thiourea. The multiple nickel sulfide phases and rGO synergistically improve the electrochemical performance of the supercapacitor electrode, which shows high specific capacity of 609.4C g(-1) at current density of 1 A g(-1). The electrode can keep a good stability with coulombic efficiency of as high as 99.5% after 1000 cycles. The small solution and charge transfer resistances of 0.42 and 0.24 0 indicate the positive synergistic effects of the multiple phases of NiS and graphene on the electrochemical performance.