Faster charge transfer rate of Ni-doped MoS2 and reduced graphene oxide based advanced anode in sodium-ion batteries

Sodium-ion batteries (SIBs) exhibit stable and safer battery behavior during long charge/discharge cycles over widely adopted lithium-ion batteries (LIBs). Herein, we demonstrated the approach and effects of doping in a composite of reduced graphene oxide with 2% nickel-doped molybdenum disulfide (G/Ni 2% MoS 2 ) synthesized via a solvothermal route. G/Ni 2% MoS 2 composite promotes accelerated reaction kinetics due to the integration of Ni 2+ ion which generates an extra redox active site for improved charge storage. Moreover, rGO focusing the structural stability by buffering volume expansion during sodiation/de sodiation. From electrochemical impedance spectroscopy (EIS) analysis, G/Ni 2% MoS 2 composite depicts improved reaction kinetics with faster charge transfer time (τ) (2.318 ms) as compared to G/Ni 0% MoS 2 (2.892 ms). An improved discharge specific capacity of G/Ni 2% MoS 2 (307 mAh.g −1 ) reflects better charge storage along with superior cyclic stability (500 cycles) in contrast to G/Ni 0% MoS 2 . Based on Dunn’s model, diffusive and capacitive contributions of G/Ni 0% MoS 2 and G/Ni 2% MoS 2 are calculated. The battery graded nature of G/Ni 2% MoS 2 (b-value = 0.39) and G/Ni 0% MoS 2 (b-value = 0.52) composites are evaluated from b-value graphs based on Power law. Overall, G/Ni 2% MoS 2 composite as an anode material depicts stabilized crystal structure, rapid ionic/electronic mobility and upgraded Na + accumulation which imitates the innovation of this work.