Cooperative catalytic interface accelerates redox kinetics of sulfur species for high-performance Li-S batteries

The high theoretical energy density and low cost make lithium-sulfur (Li-S) batteries an ideal choice for next-generation energy storage devices. However, the slow kinetics cause the reaction process to be incomplete and low reaction rate. To solve this problem, a novel cooperative catalytic interface with fine molecular regulation mechanism is designed by taking advantage of the electronic correlation between the catalyst and polysulfides (LiPSs), which multi-step process contains chemical adsorption, catalytic activity center and lithium-ion transfer. The cooperative catalytic interface greatly accelerates the kinetics of LiPSs conversion, precipitation of Li2S in discharging, and insoluble Li2S decomposition in charging process. Therefore, the [email protected]3N4-based cathode exhibits an outstanding electrochemical performance. Even under the condition of high sulfur loading of 6.0 mg cm−2, the constructed Li-S batteries demonstrate the ultralow capacity decay rate of 0.025% per cycle up to 1000 cycles. Moreover, its catalytic mechanism is deeply analyzed through DFT theory and in(ex)-situ technologies. This work will open a new window for the rational design of Li-S electrocatalyst based on cooperative interface.