Electrospun P2-type Na_2/3(Fe_1/2Mn_1/2)O₂ Hierarchical Nanofibers as Cathode Material for Sodium-Ion Batteries

Sodium-ion batteries can be the best alternative to lithium-ion batteries, because of their similar electrochemistry, nontoxicity, and elemental abundance and the low cost of sodium. They still stand in need of better cathodes in terms of their structural and electrochemical aspects. Accordingly, the present study reports the first example of the preparation of Na_2/3(Fe_1/2Mn_1/2)­O₂ hierarchical nanofibers by electrospinning. The nanofibers with aggregated nanocrystallites along the fiber direction have been characterized structurally and electrochemically, resulting in enhanced cyclability when compared to nanoparticles, with initial discharge capacity of ∼195 mAh g^–1. This is attributed to the good interconnection among the fibers, with well-guided charge transfers and better electrolyte contacts.