Synthesis of a Sodium-Ion Cathode Material Na3Fe2(SO4)3F with the Help of Fluorine Element

F cathode exhibits an exceptionally high voltage of 3.77 V, excellent discharge capacity (102 mAh/g at 0.1C), and good rate capability. This material broadens the research directions for cathode materials and holds promise as a foundation for the further development of high-performance sodium-ion batteries.