Solvothermal synthesis of ternary Cu2O-CuO-RGO composites as anode materials for high performance lithium-ion batteries

Ternary copper oxides/reduced graphene oxide (Cu2O-CuO-RGO) composites were successfully synthesized in situ by a self-assembly solvothermal method in a water-ethanol mixture and used directly as the anode material for lithium ion batteries. The Cu2O-CuO-RGO composites delivered a reversible capacity of 842.5 mAh g(-1) after 80 cycles at a current density of 100 mA g(-1), and after every 10 cycles at current densities of 100, 200, 500, 1000, 2000, 5000 and 100 mA g(-1), respectively, the specific capacities of the composites were approximately 840, 723, 511, 402, 336, 224, and 703 mAh g(-1), respectively. The improved electrochemical performance of the composites is closely related to its sandwich structure, with multicomponent Cu2O-CuO nanospheres adhering tightly to both sides of RGO nanosheets. This structure could shorten the transport pathways for both electrons and lithium ions, prevent the RGO nanosheets from stacking, enhance the electrical conductivity and accommodate the volume expansion that occurs during prolonged cycling. (C) 2016 Elsevier Ltd. All rights reserved.