Bifunctional artificial sodium polysulfide mediators boosting the sodium storage performance of the Fe3O4 anode

Abstract

Artificially incorporating sodium polysulfides into Fe₃O₄@rGO anodes enables in situ formation of uniformly dispersed Cu₂S nanocrystals, acting as reversible redox-active sites to enhance capacity and as kinetically favourable interparticle bridges to accelerate Na⁺ diffusion. This work demonstrates a simple strategy for interparticle engineering in sodium-ion batteries using multifunctional polysulfide mediators.