Molten salt synthesis of CoFe2O4 and its energy storage properties

In this article, we report simple and scalable one-pot molten salt synthesis of CoFe2O4 as electrode material for Lithium ion batteries. X-ray diffraction studies along with Rietveld analysis showed a pure phase of CoFe2O4 with space group Fd-3m and crystallite size of 54 nm. As an anode material CoFe2O4 showed high initial discharge/charge capacity of 1556/1093 mA h g(-1) and a reversible capacity of 926 mA h g(-1) after 30 cycles with columbic efficiency of 99%. A relatively high reversible capacity of 594 mA h g(-1) was observed at high current density of 1C (916 mA g(-1)) which shows the better reversibility of CoFe2O4 at high current density. As the current was reduced to 0.1C reversible capacity of 899 mA h g(-1) was retained suggesting high rate performance of CoFe2O4. The long-term stability test, carried out using galvanostatic charge/discharge (GC) at a current density of 0.5C, showed a reversible capacity of 369 mA h g(-1) at the end of 200th cycle. The structural and morphological evaluation of the sample after cycling, using ex-situ X-ray diffraction and ex-situ transmission electron microscopy, confirmed structural degradation and formation of metal nanoparticles, Li2O and amorphous nature of electrode material. The one-pot molten salt synthesis approach is quite simple and can be extended for large-scale production of electrode materials.

Automated summary

In this article, a simple and scalable one-pot molten salt synthesis of CoFe2O4 as electrode material for Lithium ion batteries was reported, showing high reversible capacity and rate performance at different current densities. Furthermore, the structural and morphological evaluation using ex-situ X-ray diffraction and ex-situ transmission electron microscopy confirmed structural degradation and formation of metal nanoparticles, Li2O, and amorphous nature of the electrode material after cycling. The one-pot molten salt synthesis approach was shown to be simple and suitable for large-scale production of electrode materials.