Amorphizing Iron Molybdate as a High‐Capacity Cathode for Lithium Metal Batteries Enabled by Multiple Insertion Reactions in the Metastable Structure

Abstract The rising energy demand for electric vehicles and energy storage has revived interest in lithium‐metal batteries (LMBs). However, present LMBs still mainly rely on conventional lithium‐ion batteries (LIBs) cathodes (e.g., LiFePO 4 and LiNi 1/3 Mn 1/3 Co 1/3 O 2 ) with limited reversible capacity (≈150 to ≈190 mAh g −1 cathode ), necessitating the paradigm to achieve a new host with abundant Li + accommodation sites. Herein, it is proposed a high‐capacity amorphizing iron molybdate cathode a‐Fe 2 (MoO 4 ) 3 (a‐FMO), which can reversibly unlock Fe 3+ /Fe 2+ and Mo 6+ /Mo 4+ redox insertion reactions in the metastable structure. Different from its parent crystal and stoichiometric oxides mixtures, a‐FMO, with its inherent metastable structure, can not only augment the lithium storage capacities with fully activated redox centers, but also attenuate the lattice confinements for Li …