Interface engineering-induced enhancements in sodium-ion batteries: A nexus of ZnS nanoparticles and reduced graphene oxide for augmented storage and conductivity

Due to the inherent sluggish kinetics and the pronounced volumetric expansion of zinc sulfide (ZnS), it has become a prevalent modification strategy to regulate its morphology and composite with graphene for using ZnS as anodes in sodium-ion batteries (SIBs). Nevertheless, the elucidation of mechanisms underpinning the electrochemical performance facilitated by graphene incorporation remains scant. To further describe the synergistic mechanism, the ultrafine ZnS nanoparticles anchored on reduced graphene oxide (rGO) were synthesized through a simple solvothermal method . Research shows that the ZSG (ZnS nanoparticles-reduced graphene oxide composite) electrode suggests superior rate capability, maintaining a reversible specific capacity of 228.6 mAh·g −1 upon returning from a high current density of 5 A·g −1 . Furthermore, the nanoscale integration of ZnS particles with rGO synergistically mitigates the structural expansion of the ZSG electrode encountered during cycling, thereby decelerating the degradation of cyclic performance. Insights gleaned from first-principles calculations and comprehensive electrochemical evaluations reveal that the built-in electric field, engendered within the composite architecture, substantially augments charge transfer ability and mitigates the energy barriers impeding sodium ion (Na + ) diffusion accordingly. Consequently, the methodology adopted for synthesis and the synergistic modification mechanism can proffer a reference for the design of advanced anode materials in SIBs. • Ultrafine ZnS nanoparticles on rGO synthesized via simple solvent method. • the sodium storage mechanism of ZSG electrode was further explored. • Internal electric fields and rGO synergize to enhance ZnS conductivity. • The addition of rGO reduces energy barriers, speeding up sodium ion transport. • Improved rate performance, cycling stability, and higher specific capacity.