Grapevine-like high entropy oxide composites boost high-performance lithium sulfur batteries as bifunctional interlayers

Abstract

Lithium-sulfur batteries (LSBs) with high energy densities have been demonstrated the potential for energy-intensive demand applications. However, their commercial applicability is hampered by hysteretic electrode reaction kinetics and the shuttle effect of lithium polysulfides (LiPSs). In this work, an interlayer consisting of high-entropy metal oxide (Cu0.7Fe0.6Mn0.4Ni0.6Sn0.5)O4 grown on carbon nanofibers (HEO/CNFs) is designed for LSBs. The CNFs with highly porous networks provide transport pathways for Li+ and e−, as well as a physical sieve effect to limit LiPSs crossover. In particular, the grapevine-like HEO nanoparticles generate metal-sulfur bonds with LiPSs, efficiently anchoring active materials. The unique structure and function of the interlayer enable the LSBs with superior electrochemical performance, i.e., the high specific capacity of 1381 mAh g−1 at 0.1 C and 561 mAh g−1 at 6 C. This work presents a facile strategy for exploiting high-performance LSBs.

Keywords

• Electrospun carbon nanofibers
• Grapevine-like morphology
• Hierarchical physical sieve effect
• High-entropy induced chemisorption
• Lithium-sulfur battery