Elevating Lithium-Sulfur Battery Durability through Samarium Oxide/Ketjen Black Modified Separator

Lithium-sulfur batteries have garnered significant attention as a promising next-generation battery technology due to their potential for high energy density. However, their practical application is hampered by slow reaction kinetics and the shuttle effect of lithium polysulfide intermediates. In this context, the authors introduce a pioneering solution in the form of a novel porous carbon nanostructure modified with samarium oxide, denoted as Sm₂O₃/KB. The material has a highly polar surface, allowing lithium polysulfide to be chemisorbed efficiently. The unsaturated sites provided by the oxygen vacancies of Sm₂O₃ promote Li₂S nucleation, lowering the reaction energy barrier and accelerating Li₂S dissolution. The porous structure of Ketjen Black provides a highly conductive channel for electron transport and effectively traps polysulfides. Meanwhile, the batteries with Sm₂O₃/KB/PP spacers exhibited remarkable electrochemical performances, including a low-capacity decay rate of only 0.046 % for 1000 cycles at 2 C and an excellent multiplicative performance of 624 mAh g^-1 at 3 C. This work opens up a new avenue for the potential use of rare-earth-based materials in lithium-sulfur batteries.