Molybdenum-Doped Nickel Disulfide (NiS2:Mo) Microspheres as an Active Anode Material for High-Performance Durable Lithium-Ion Batteries

Transition-metal sulfides (TMSs) are promising anode materials for lithium-ion batteries (LIBs) as they exhibit anomalously high specific capacities. However, the electrodes made on TMSs possess low electronic conductivity and poor specific capacity retention, which hinder their application in LIBs. Herein, we report a one-step, simple, hydrothermal technique for synthesizing molybdenum-doped nickel disulfide (NiS2:Mo) microspheres with varying Mo contents (0, 5, and 10 wt %) and their performance as anode materials in LIBs. Mo doping was found to improve the electronic conductivity, structural stability, and reduce charge transfer resistance between the electrode/electrolyte interface of NiS2 microspheres, thereby achieving a superior electrochemical performance in LIBs. The anode made of NiS2:Mo microspheres with 5 wt % Mo registered a maximum specific capacity and cycling durability. It delivered an outstanding initial specific capacity of 1605 mAh g(-1) at 0.1 Ag-1 and exhibited exceptional cycling stability with a reversible discharge capacity retention of 713.3 mAh g(-1) after 120 cycles and Coulombic efficiency of 98.42%. Such exceptionally high specific capacity and high charge-discharge capacity retention of the NiS2:Mo (5%) microspheres indicate that the material is a promising anode material for LIBs and other advanced energy storage applications.