Revealing structure correlation between ionic liquid and metal-organic framework matrix.

Solid-state batteries are rising rapidly in response to the fast-increasing energy demand. Metal-organic framework (MOF) loaded with ionic liquids has brought new opportunities for solid-state batteries owing to its good interfacial compatibility and high ionic conductivity. MOF-808 is selected to be filled with Li-contained ionic liquid for structure and ion dynamics investigation using nuclear magnetic resonance (NMR) and X-ray diffraction. This study finds that the introduced ionic liquid would partially soften the matrix of MOF-808 and thus yield amorphous phase. By selective isotope replacement under cycling symmetric Li metal cell, Li ion is observed to mainly go cross ionic liquid in the open channel of matrix under potential polarization.