Solid-state electrolytes based on metal-organic frameworks for enabling high-performance lithium-metal batteries: Fundamentals, progress, and perspectives

Solid-state electrolytes (SSEs) with flame retardancy and good adaptability to lithium-metal anodes can have great potential in enabling high safety and high energy density lithium-metal batteries. In addition to optimize the composition/structure of current three main types of SSEs including inorganic SSEs, polymeric SSEs, and inorganic/polymer composite SSEs, massive efforts are under way to seek for new SSE formulations. Recently, metal-organic frameworks (MOFs), a type of crystalline inorganic–organic materials with the structural features of rich porous, ordered channels, tunable functionality, are emerging as a research hotspot in the field of SSEs, which have attracted tremendous efforts. Based on the latest investigations, in this paper, a systematic overview of the recent development in MOFs-based SSEs (MSSEs) for lithium-metal batteries is presented. Classification and compositions, development history, fabrication approaches, and recent progress of five main types of MSSEs are comprehensively reviewed, and the roles of MOFs in MSSEs including ionic conductors, ionic transport carriers, and added fillers are highlighted. Moreover, the main challenges are analyzed and the perspectives of MSSEs are also presented for their future research and development. This review not only contributes to the study of new systems of solid-state electrolytes, but also for further development of electrified transportation.