A supercritical methanol route for the synthesis of sodium iron oxide submicron plates for use as a cathode material for sodium-ion batteries

摘要

Highly crystalline, phase-pure NaFeO2 submicron plates are synthesized using a facile and simple super-critical methanol route. The synthesized NaFeO2 submicron plates are 160 to 680 nm in width and 90 nm in thickness. Because of their two-dimensional structure, the NaFeO2 submicron plates exhibit excellent electrochemical performance with smaller polarization compare to micron-sized NaFeO2 particles synthesized using a solid-state method; the initial charge capacity is 94 mAh g(-1) at 10 mA g(-1) and high rate capacity of 34 mAh g(-1) at 50 mA g(-1), which is 180% higher than that of solid-state synthesized NaFeO2. The enhanced charge-discharge characteristics are attributed to the low charge transfer resistance and high Na-ion diffusivity. (C) 2017 Elsevier B.V. All rights reserved.