EDTA-Co(II) sodium complex derived Co(OH)2/Co3O4/Co nanoparticles embedded in nitrogen-enriched graphitic porous carbon as lithium-ion battery anode with superior cycling stability

Abstract

Transition metal hydroxides (TMHOs) can be applied either as pseudocapacitive materials for high-power supercapacitors or as positive electrode materials for rechargeable alkaline batteries. However, TMHOs have been seldom studied as anode materials for lithium-ion batteries (LIBs) although they are very competitive similarly to electrochemical active metal oxides. Here, we reported a facile synthesis of Co(OH)2/Co3O4/Co nanoparticles embedded in nitrogen-enriched graphitic porous carbon using EDTA-Co(II) sodium complex as the precursor. The composite delivers a high reversible capacity of 553 mAh g−1 at a current density of 100 mA g−1, and remains around 540 mA h g−1 after 300 cycles without significant fading. Moreover, the composite demonstrates high-rate performance as well, a high specific capacity of around 280 mAh g−1 can still be achieved at 800 mA g−1. Overall, the reported composite and synthesis methodology may stimulate further research of TMHOs and their composite as excellent energy-storage anode materials for LIBs.