High rate performance and stabilized cycle life of Co2+-doped nickel sulfide nanosheets synthesized by a scalable method of solid-state reaction

In this work, a “Co 2+ doping” new strategy is proposed to promote the high rate performance and extend the cycling life of nickel-based sulfides. The Co 2+ doped Ni 3 S 4 nanosheets are prepared at mild conditions by a scalable method of solid-state reaction. The preparation of doped sulfide includes two steps: 1) formation of amorphous Co 2+ doped nickel sulfide nanosheets by grinding the mixture of raw materials at room temperature in a mortar; 2) crystallization to Co 2+ doped Ni 3 S 4 nanosheets at 150 °C for 5 h. Due to the doped Co 2+ ions, the as-prepared sulfide presents promoted high rate performance and prolonged cycling life. It should be pointed out that the “Co 2+ doping” strategy for the electrochemical stabilization of nickel-based sulfides could be easily scaled up due to the large-scale preparation characteristics and high performance of produced material.