Synthesis and electrochemical properties of nickel sulfide/carbon composite as anode material for lithium‐ion and sodium‐ion batteries

Transition metal sulfides have been considered a novel anode material for lithium-ion and sodium-ion batteries (LIBs/SIBs). However, their practical applications have been limited by their relatively poor cyclic stabilities and low rate performances. This work synthesized carbon-coated nickel sulfide (NiS) composites with a core-shell structure for high-performance LIBs and SIBs by a solvothermal method. The one-step synthesis of nickel sulfide and carbon at a low temperature can affect the thin homogeneous carbon coating, the buffer volume, and the sulfur dissolution of NiS nanoparticles. Due to small particle size dominance, desirable structural flexibility, and core-shell architecture, the as-prepared nickel sulfide/carbon composites showed substantial enhancement in LIBs and SIBs. The nickel sulfide/carbon composite electrodes displayed a high reversible discharge capacity of around 500 and 360 mAh/g after 50 cycles for LIBs and SIBs. The prepared NiS anode materials deliver the enormous potential for developing huge lithium/sodium storage.