Towards superior lithium–sulfur batteries with metal–organic frameworks and their derivatives

Abstract

Lithium–sulfur batteries (LSBs) are one of the most promising energy storage devices in the future due to their high theoretical specific capacity (1675 mA·h·g–1) and energy density (2600 W·h·kg–1). However, the severe capacity decay caused by the shuttle effect of polysulfides needs to be addressed before the practical application. Metal–organic frameworks (MOFs) and their derivatives are known for their large specific surface area, high porosity, abundant functional groups, and good chemical stability. Thus, they have been widely investigated in LSBs. This review introduces the principles of the LSBs and origination of the shuttle effect first summarizes various methods of limiting polysulfide diffusion by MOFs and their derivatives both in cathodes and separators, and provides an in-depth discussion of the immobilization mechanisms, which helps to understand the advantages and disadvantages of each method. The mechanisms, such as structure and pore size tuning, chemical absorption, and catalytic conversion, are discussed. Finally, based on the method of MOFs and their derivatives to inhibit the diffusion of polysulfides, the application prospect of MOFs and their derivatives in LSBs technology are proposed.