ZnO/ZnS heterostructure in N-doped porous carbon for anchoring-diffusion-conversion of polysulfides for high-performance lithium-sulfur batteries

The shuttle effect of polysulfides is one of the key factors hindering the commercialization of lithiumsulfur batteries(LSBs).Owing to their high conductivity and advantageous structure,heterostructures can be used in sulfur fixation and catalysis of LSBs.In this study,a flower-shaped ZnO/ZnS heterostructure on a nitrogendoped porous carbon(NPC) sulfur host was designed.The ZnO/ZnS heterostructure regulates the electronic structure of the material and exhibits higher metal-like properties.Moreover,the ZnO/ZnS heterostructure combines the strong adsorption property of ZnO and the high catalytic ability of ZnS to realize the anchoring-diffusionconversion of lithium poly sulfides(LiPSs).Results reveal that the developed ZnO/ZnS@NPC/S cathode has excellent electrochemical performance in LSBs,achieving a high discharge specific capacity of 1365.3 mAh·g^(-1) at 0.1C and excellent rate capability(719 mAh·g^(-1) at 2C;the capacity decay rate is only 0.042% per cycle after 1000 cycles).Even under a high sulfur loading-E/S(electrolyte/sulfur)ratio of 5.1 mg·cm^(-2)-6 μl·mg^(-1),a high specific capacity of 723.7 mAh·g^(-1) is maintained after 60 cycles.This study provides a new strategy for a multifunctional sulfur host that can effectively alleviate the shuttle effect of LiPSs and improve the utilization of sulfur active substances.