具有协同吸附-催化效应的莫特-肖特基异质结构修 饰隔膜助力锂硫电池

The low sulfur usage, strong shuttle effect, and dilatory redox processes limit the practical application of lithium-sulfur batteries (LSBs). The method of separator modification with a unique Mott-Schottky heterostructure used in this work significantly alleviates these issues. This unique structure is synthesized by in situ polymerizing the conductive polymer polypyrrole (PPy) on the surface of Bi2MoO6 nanosheets to form Bi2MoO6-PPy nanosheets. This unique heterostructure can minimize the redox energy barrier on polysulfides due to the strong adsorption effect, high catalytic activity, and built-in electric field of Bi2MoO6-PPy nanosheets. The battery demonstrates good cycling stability when assembled with the functional separator modified by Bi2MoO6-PPy nanosheets, with an ultralow capacity decay of 0.045% per cycle over 500 cycles at 2 C. Furthermore, even with a high sulfur loading (7.5 mg cm−2), the battery retains an areal capacity of 6.3 mA h cm−2 at 0.2 C after 80 cycles. As a result, the suggested Mott-Schottky heterostructure-based Bi2MoO6-PPy nanosheets-modified separator (Bi2MoO6-PPy@PP separator) successfully suppresses the shuttle effect, providing an effective strategy for deploying efficient LSB.