Glassy Metal–Organic Framework-Based Solid-State Electrolytes: Advance, Challenge, and Emerging Opportunities

Glassy metal–organic frameworks (MOFs) are amorphous porous materials constructed by inorganic metal ions and organic ligands. Owing to the unique features of abundant unsaturated metal sites, grain-boundary-free and isotropic attributes, glassy MOFs are emerging as a type of promising material platform in energy storage, especially as solid-state electrolytes. In this review, the mechanisms that promote ionic migration/conductivity and suppress the formation of lithium dendrites for glassy MOF-based electrolytes are briefly summarized. Different types of glassy MOF-based electrolytes are systematically introduced. Moreover, the influences of multiple factors on the performance of glassy MOF-based electrolytes are discussed, including the structural characteristics, pore sizes, the addition of ionic liquids, compositing with polymers, and the electronic effect. Finally, new insights and prospects for future development of glassy MOF-based electrolytes are presented to inspire innovative approaches for the commercial applications of MOF glass-based lithium metal batteries.