Ni Single Atoms on MoS 2 Nanosheets Enabling Enhanced Kinetics of Li-S Batteries.

The practical application of Li-S batteries is seriously hindered due to its shuttle effect and sluggish redox reaction, which requires a better functional separator to solve the problems. Herein, polypropylene separators modified by MoS 2 nanosheets with atomically dispersed nickel (Ni-MoS 2 ) are prepared to prevent the shuttle effect and facilitate the redox kinetics for Li-S batteries. Compared with pristine MoS 2 nanosheets, Ni-MoS 2 nanosheets exhibit both excellent adsorption and catalysis performance for overcoming the shuttle effect. Assembled with this novel separator, the Li-S batteries exhibit an admirable cycling stability at 2 C over 400 cycles with 0.01% per cycle decaying. In addition, even with a high sulfur loading of 7.5 mg cm -2 , the battery still provides an initial capacity of 6.9 mAh cm -2 and remains 5.9 mAh cm -2 after 50 cycles because of the fast convention of polysulfides catalyzed by Ni-MoS 2 nanosheets, which is further confirmed by the density functional theory (DFT) calculations. Therefore, the proposed strategy is expected to offer a new thought for single atom catalyst applying in Li-S batteries.