MOF-Enhanced Sulfur-Containing Polymer for Boosting Lithium-Ion Diffusion in Lithium–Sulfur Battery

Organic sulfur batteries, with their high theoretical specific capacity and energy density, have emerged as promising candidates. However, their application is hindered by challenges in lithium-ion diffusion within dense molecular structures, particularly in polymers with high sulfur content. In this study, we report the synthesis of a novel MOF-based sulfur-containing polymer, MOF808-D@PS, designed to enhance lithium-ion diffusion and optimize electrochemical performance. The introduction of N-containing organic ligands within the MOF architecture led to a 103-fold increase in the lithium-ion diffusion coefficient compared to unmodified sulfur-containing polymer cathodes. The MOF808-D@PS electrode, with a sulfur content of 69.4%, exhibited exceptional electrochemical performance, achieving a capacity of 1213 mAh g–1 at 0.3 C. Even at high rate of 5 C, the material retained a significant capacity of 726 mAh g–1. These results demonstrate the potential of MOF-based strategies in advancing the design of high-rate sulfur-containing polymer electrodes, providing a pathway toward the commercial viability of lithium-sulfur (Li-S) batteries.