Chemical Regulation of Microenvironment in Metal-organic Frameworks for Lithium-sulfur Batteries

Lithium-sulfur batteries (LSBs) are considered to be one of the most promising new generation energy storage device owing to the high theoretical specific capacity, low cost, and environmental friendliness of sulfur. However, there are still some unsolved critical issues in LSBs, such as slow redox kinetics, shuttle effect caused by dissolution and diffusion of lithium polysulfides (LiPSs), as well as volume changes in electrodes during charge/discharge processes. which result in poor capacity and cycling stability, severely hinder the practical application of LSBs. Metal-organic frameworks (MOFs) have highly tunable pore microenvironment, and their chemical adsorption and catalytic abilities towards guest molecules, such as polysulfides, can be precisely controlled at the molecular level by regulating the metal centers/clusters and organic ligands. Therefore, applying MOFs to LSBs can effectively capture, block and accelerate the catalytic conversion of polysulfides, thus inhibiting the shuttle effect and improving the electrochemical performance of LSBs. This review summarizes various high performance interlayer materials, cathode materials and multifunctional separator materials based on MOFs developed by regulating the pore microenvironment of MOFs, and analyzes the mechanism of regulating MOFs’ microenvironment affecting the performance of LSBs. Finally, the problem and development direction of MOFs materials applicable to high performance LSBs are proposed.