MnO2 Modified Reduced Graphene Oxide for Lithium-Sulfur Batteries with Improved High-Rate Cycling Stability

A facile and mild method was used to in situ grow MnO2 on RGO (reduced graphene oxide). This MnO2 modified RGO hybrid was designed as a host for sulfur and served as a cathode for lithium-sulfur batteries. The batteries with high loading of sulfur (similar to 70%) show high initial capacity compared with the one without MnO2, and excellent improved cycling performance at high rate of 1C, with a capacity retention of 87% after 300 cycles. The higher performance may benefit from MnO2 as a semiconductor which can facilitate electron transportation and provide migration pathways for Li+ by its tunnels structure, and as an anchor and transfer mediator to chemically trap polysulfides.