Core–Shell Tandem Catalysis Coupled with Interface Engineering For High‐Performance Room‐Temperature Na–S Batteries
Daliang Fang, Tanmay Ghosh, Shaozhuan Huang, Ye Wang, Jianbei Qiu, Xuhui Xu, Hui Ying Yang
Abstract
Abstract The sluggish redox kinetics and shuttle effect seriously impede the large application of room‐temperature sodium–sulfur (RT Na–S) batteries. Designing effective catalysts into cathode material is a promising approach to overcome the above issues. However, considering the multistep and multiphase transformations of sulfur redox process, it is impractical to achieve the effective catalysis of the entire S 8 →Na 2 S x →Na 2 S conversion through applying a single catalyst. Herein, this work fabricates a nitrogen‐doped core–shell carbon nanosphere integrated with two different catalysts (ZnS‐NC@Ni‐N 4 ), where isolated Ni–N 4 sites and ZnS nanocrystals are distributed in the shell and core, respectively. ZnS nanocrystals ensure the rapid reduction of S 8 into Na 2 S x (4 < x ≤ 8), while Ni–N 4 sites realize the efficient conversion of Na 2 S x into Na 2 S, bridged by the diffusion of Na 2 S x from the core to shell. Besides, Ni–N 4 sites on the shell can also induce an inorganic‐rich cathode–electrolyte interface (CEI) on ZnS‐NC@Ni‐N 4 to further inhibit the shuttle effect. As a result, ZnS‐NC@Ni‐N 4 /S cathode exhibits an excellent rate‐performance (650 mAh g −1 at 5 A g −1 ) and ultralong cycling stability for 2000 cycles with a low capacity‐decay rate of 0.011% per cycle. This work will guide the rational design of multicatalysts for high‐performance RT Na–S batteries.