One-step electrochemical preparation of graphene-based heterostructures for Li storage

Abstract

We report a facile method to prepare nanoarchitectured metal oxides/graphene hybrids as both positive and negative electrodes for Li-ion batteries. The metal oxides/graphene hybrids were synthesized by deposition of metal oxides and exfoliation of graphene sheets in a one-step electrochemical process. The hybrid electrodes showed high specific capacities with excellent cycling stability. For example, the Fe₂O₃/graphene anode was able to deliver a discharge capacity of up to 894 mA h g⁻¹ during the 50^th cycle at 0.3 C. Co₃O₄/graphene depicted a discharge capacity of 880 mA h g⁻¹ during the 40^th cycle at 0.3 C. The V₂O₅/graphene cathode delivered a discharge capacity of 208 mA h g⁻¹ during the 100^th cycle at 6.8 C.