Synergistic Interaction\nof Strongly Polar Zinc Selenide\nand Highly Conductive Carbon Nanoframeworks Accelerates Redox Kinetics\nof Polysulfides

Lithium–sulfur batteries (LSBs) have become strong\ncompetitors\nin secondary battery systems because of their superior theoretical\ncapacity and energy density. However, due to the serious shuttle effect\nof soluble long-chain lithium polysulfides (LiPSs) and the slow solid–solid\nreaction kinetics, LSBs face some specific challenges, such as a short\ncycle life and low rate performance. The introduction of selenide/carbon\ncomposites derived from zeolite imidazolate frameworks (ZIFs) into\nseparator coatings is a direct and effective solution to the aforementioned\nproblems. Here, a zinc selenide/carbon catalyst material (ZnSe@C)\nwas constructed and employed to modify commercial polypropylene (PP)\nseparators to accelerate the conversion of intermediates. The highly\npolar ZnSe effectively fixes the active material on the cathode side\nby transferring electrons between elements with LiPSs and improves\nthe utilization rate of sulfur. Concurrently, the highly conductive\ncarbon nanoskeleton generated following the pyrolysis of ZIF-8 ensures\nthe rapid transfer of charges during the catalytic reaction. The prepared\nZnSe@C has a large specific surface area (250.07 m<sup>2</sup> g<sup>–1</sup>) and mesoporous ratio (78.03%), which not only enhances\nadsorption and catalysis but also promotes the penetration of the\nelectrolyte and the transport of Li<sup>+</sup>. Based on this, ZnSe@C/PP\nseparator cells exhibit a low average capacity decay rate of 0.051%\nper cycle after 500 cycles at 1 C.