“…Among them, nickel sulfides with multiple distinct phases, such as α-NiS, β-NiS, NiS 2 , Ni 3 S 2 , Ni 3 S 4 , Ni 7 S 6 , and Ni 9 S 8 , possess ultrahigh conductivity, Faradic reaction activities, and chemical stability. NiS 2 , a pyrite structure, has been reported in hybrid supercapacitors with excellent electrochemical ability. , Xu et al proposed NiS 2 /C particles, exhibiting 1872 F g –1 capacitance at 1 A g –1 . Ghosh et al fabricated carbon-coated NiS 2 with a capacitance of 2212 F g –1 at 2 A g –1 .…”