Facile synthesis of Co3O4 by molten salt method and its Li-storage performance

Abstract

We synthesized Co₃O₄ compounds using different molten salts such as LiNO₃:LiOH, LiNO₃:LiCl, NaNO₃:KNO₃, KCl and studied their morphology and Li-storage properties. Eleven samples were prepared at various temperatures ranging from 180 °C to 710 °C and evaluated the effect of different Co-salts such as Co-sulphate, Co-acetate and Co-hydroxide on crystal growth and Li-storage performance. The obtained Co₃O₄ powders were characterized by a variety of techniques. Li-storage performance studies on Co₃O₄ prepared by different Co-salts show reversible capacity values in the range, 778 to 1090 mA h g⁻¹ at a current rate of 60 mA g⁻¹ and at the end of the 40th cycle. Among the effects of preparation temperature, Co₃O₄ prepared at 510 °C showed the best combination of capacity and sustainability. Co₃O₄ prepared from different cobalt sources among Co-sulphate delivered the highest and most stable capacity with the smallest fading. We report the growth, reaction mechanism and storage performance of different Co₃O₄.