Metal–organic frameworks as separators and electrolytes for lithium–sulfur batteries

Abstract

Due to high energy density and low cost, lithium–sulfur batteries (LSBs) have been regarded as the next generation of energy storage systems. As indispensable parts of LSBs, separators and solid electrolytes play an important role in inhibiting dendrite growth and eliminating short-circuit risks. Their development can fundamentally improve the performance of LSBs. In recent years, metal–organic frameworks (MOFs), as porous crystalline inorganic–organic materials with high porosity, uniform pore size distribution, customizable structure, and easy functionalization, are used as molecular sieves to uniformly deposit lithium ions and combine high-soluble solid solution polysulfides (PSs), which have become an emerging research direction. In this review, we are devoted to summarizing the design strategy of MOF-based separators and electrolytes based on MOFs and MOF-derived materials for LSBs. By discussing the pioneer works, both opportunities and challenges in each category are presented. Additionally, some design principles for MOF-based separators and MOF-based electrolytes, as well as the future directions for further development are provided.