Enabling Synergistic Adsorption–Catalysis in Li–S Batteries by MOF-Derived Cobalt-Doped Porous Carbon

Lithium–sulfur (Li–S) batteries offer high theoretical energy density but suffer from sluggish polysulfide conversion kinetics and the severe shuttle effect, leading to rapid capacity decay and poor rate performance. Herein, a cobalt-doped hierarchically porous carbon (Co-HPC) is rationally designed via pyrolysis of Co-doped Zn-BTC metal–organic frameworks (MOFs) to enable synergistic polysulfide adsorption and catalytic conversion. The resulting Co-HPC features a conductive carbon framework, hierarchical porosity, and uniformly dispersed cobalt nanoparticles, providing abundant active sites for polysulfide regulation. Benefiting from enhanced electrolyte wettability, strong polysulfides affinity, and accelerated redox kinetics, Li–S cells employing Co-HPC cathodes exhibit significantly reduced polarization and improved reaction reversibility. As a result, the Co-HPC-based cell delivers a high discharge capacity of 934.01 mAh/g at 0.1 A/g, an outstanding rate capability up to 1 A/g, and considerable long-term cycling stability with a minimal decay rate of 0.12% per cycle over 500 cycles at 0.5 A/g. This work demonstrates an effective strategy to integrate adsorption and catalysis within MOF-derived carbon, offering insights into the rational design of advanced sulfur cathodes for high-performance Li–S batteries.