Engineering the interface between separators and cathodes to suppress polysulfide shuttling in lithium-sulfur batteries

Lithium-sulfur batteries have attracted extensive attention because of their high theoretical specific energy storage capacity and energy density. However, the shuttling of polysulfides greatly hinders their practical use. Many studies show that engineering the interface between separators and cathodes is an effective strategy to solve this problem. Ways to inhibit the shuttling can be divided into physical blocking, chemical adsorption, and catalysis. Among the interfacial materials, carbon materials have attracted enormous attention due to their high electrical conductivity, large specific area, and high pore volume. However, their non-polarity makes it impossible for them to bind polysulfides tightly and heteroatoms/functional groups are incorporated in them or highly polar materials are composited with them in the design of the interfacial materials. In addition, the catalytic effect of the carbon in the polysulfide conversion is believed to be very important in effectively suppressing the shuttling. This review focuses on the detailed strategies and functions of interfacial engineering in addressing the problems and challenges in the use of lithium sulfur batteries. Finally, practical applications of lithium sulfur batteries are proposed, based on a combination of various measures including interfacial engineering.