A multifunctional LaFeO3 nanocages modified separator for propelling polysulfides chemisorption and catalytic conversion in Li-S batteries

The sluggish reaction kinetics of sulfur and the shuttle effect of intermediate polysulfides are the thorny issues for the commercialization of Li-S batteries. Commercial polypropylene separators cannot prevent the shuttling of polysulfides due to their large porosity. Therefore, the development of a novel type of separator can efficiently prohibit the transmission of polysulfides, will be beneficial to the practical application of Li-S batteries. Herein, we report a commercial membrane modified with perovskite-type LaFeO3 nanocages to block the transportation of polysulfides. Researches show that the modified multifunctional separators can not only effectively inhibit the shuttle of polysulfides, but also accelerate the reaction kinetics between S and Li2S. The electrochemical performance is greatly improved, which can be mirrored in the rate performance: 689.3 mA h g−1at 4C, and cycling performance with the capacity decay rate of only 0.0585% per cycle for 1000 cycles at 1C. More significantly, the considerable electrochemical performance is still hold under the harsh condition of lean electrolyte.