The increasing demand of the energy sources and devices are facilitating the needs of the development in the energy storage systems. Lithium-sulfur (Li-S) battery is considered as one of the most promising energy storage systems because of its high theoretical energy density (2600 Wh kg~(-1)), natural abundance leading to low cost, and their environmental friendliness. However, there are some obstacles to be solved in order to use the Li-S battery practically as follows. First, the sulfur and finally reduced product (Li_2S) have a low conductivity, impeding the rate of reactions, and hence limiting total utilization the active sulfur. Second, the shuttling of the polysulfide intermediates (Li_2S_x, 4 ≤ x ≤ 8) (Shuttle effect) leads to the low Coulombic efficiency and fast degradation of both electrodes of Li metal and Sulfur. Particularly, the transformation from liquid to solid state occurs unevenly on the surface of sulfur, leading to the aggregation, and hence a large overpotential. To overcome such the problems, some researchers have adopted various methods to prevent the shuttling of the polysulfides. Though many effective structures of the carbon and heteroatom doped carbons have been presented, it is not enough to perfectly hold the polysulfides because of the low polarity of the carbon. Recently, metal sulfides have been reported for their strong affinity with the polysulfides. However, to enhance the kinetics in the Li-S battery, it is not only important to have a high interaction between polysulfides, but should have interfacial advantages to provides nucleation sites of Li_2S_2/Li_2S, that can prevent aggregation during growth and increase electrical conductivity for fast redox reaction between polysulfide chain and solid products.
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