Exploring ionic liquid-laden metal-organic framework composite materials as hybrid electrolytes in metal (ion) batteries

This review focuses on the combination of metal-organic frameworks (MOFs) and ionic liquids (ILs) to obtain composite materials to be used as solid electrolytes in metal-ion battery applications. Benefiting from the controllable chemical composition, tunable pore structure and surface functionality, MOFs offer great opportunities for synthesizing high-performance electrolytes. Moreover, the encapsulation of ILs into porous materials can provide environmentally benign solid-state electrolytes for electrochemical devices. Due to the versatility of MOF-based materials, in this review we also explore their use as anodes and cathodes in Li- and Na-ion batteries. Finally, solid IL@MOF electrolytes and their implementation into Li and Na batteries have been analyzed, as well as the design and advanced manufacturing of solid IL@MOF electrolytes embedded on polymeric matrices has been analyzed.This work was supported by the Ministerio de Ciencia, Innovacion y Universidades (PID 2019-107468RB-C21), BIDEKO project, funded by MCIN/AEI, NextGenerationEU, PRTR and Gobierno Vasco/Eusko Jaurlaritza (IT1546-22) and ELKARTEK program. The authors also thank FCT (Fundacao para a Ciencia e Tecnologia) for financial support under the framework of Strategic Funding grants UIDB/4650/2020, UID/CTM/50025/2021, UID/FIS/04650/2021 and UID/EEA/04436/2021 and support from FEDER funds through the COMPETE 2020 Program (projects PTDC/FIS-MAC/28157/2017 and POCI-01-0145-FEDER-007688). Contract under the Stimulus of Scientific Employment, Individual Support 2020.04028 CEECIND (CC) is acknowledged. The European Commission Research and Innovation H2020-MSCA-RISE-2017 (Ref: 778412) INDESMOF project is also acknowledged