Tube‐in‐Tube Structure Design and In‐situ Growth of Fe₃C for Efficient Reaction Kinetics in Lithium‐Sulfur Batteries

Abstract

To improve the sulfur reaction kinetics and inhibit the notorious shuttle effects, a tube‐in‐tube structure decorated by carbon nanotubes (CNT) and Fe3C nanoparticles (TIT/Fe3C‐CNT) is designed as sulfur hosts for lithium‐sulfur batteries (LSBs) in this work. The construction of a tube‐in‐tube structure increases the active sites and the specific surface area of the material. Additionally, Fe3C nanoparticles can effectively adsorb the soluble lithium polysulfides and promote their catalytic conversion, thus greatly alleviating the shuttle effects. As a result of these advantages, the TIT/Fe3C‐CNT‐based cathode exhibits a high reversible capacity of 841 mAh g−1 after 200 cycles with a low decay of 0.056% per cycle at 0.5 C. This work provides a promising and reasonable approach to the rational design of a sulfur host for LSBs.