Polysulfides shuttling remedies by interface-catalytic effect of Mn3O4-MnPx heterostructure

Lithium-sulfur batteries (Li-S batteries) have attracted considerable attentions for the low cost and high theoretical energy density of sulfur. However, the Li-S batteries often undergo rapid degradation due to the severe “shuttle effect”, sluggish redox kinetics, and the insulator nature of sulfur. Herein, the Mn 3 O 4 -MnP x heterostructure was constructed via the in-situ crystallization of Mn 3 O 4 -MnP x on amorphous phosphrus (P) NPs-modified carbon nanosheets. According to the experimental test and density functional theory calculation, Mn 3 O 4 exhibits strong adsorption ability towards polysulfides. Meanwhile, MnP x dramatically catalyzes the conversion reactions between sulfur and polysulfides. The synergistic effect of Mn 3 O 4 and MnP x facilitates the facile redox kinetics and effective entrapment of polysulfides. As a result, the improved specific capacities of 1410 and 804 mA h g - 1 are obtained at 0.1 and 2 C, respectively. The capacity decay is only 0.041% per cycle over 1000 cycles at 0.5 C. This work indicuates that the interface regulation and design play an important role in advancing the electrochemical performance in Li-S batteries.