In-situ construction of Fe nanoparticles modified host materials for all-solid-state lithium-sulfur batteries with enhanced kinetic performance

Abstract

All-solid-state lithium-sulfur batteries (ASSLSBs) with high theoretical energy have attracted much attention benefiting from fundamentally addressing the adverse shuttling effect. However, the development of stably operated ASSLSBs remains a great challenge due to the low conductivity and utilization of sulfur. Inspired by the polar single-atom catalyst with 100 % theoretical atomic utilization, a simple and effective strategy is proposed to improve the electrochemical performance of ASSLSBs by introducing Fe nanoparticles into the carbon host material (Ketjen black, KB). The in-situ grown Fe nanoparticles not only enhance the conductivity of the host material, but also promotes the conversion reaction of sulfur, resulting in the improvement of sulfur utilization and redox kinetics. Therefore, the initial discharge capacity of the assembled Fe-KB/S cell reaches 976 mA h g⁻¹ at 50 mA g⁻¹, which is significantly higher than that of the KB/S cell (727 mA h g⁻¹). Moreover, the Fe-KB/S cell maintains a reversible specific capacity of 520 mA h g⁻¹ after 150 cycles, which is almost twice that of the KB/S cell. This study provides a valuable reference for the further development of ASSLSBs.