Preparation and electrochemical performances of CoO/3D graphene composite as anode for lithium-ion batteries

A CoO/3D graphene composite synthesized via hydrothermal method was used as an anode material for Li-ion batteries. X-ray diffraction, scanning electron microscopy, thermogravimetry, energy-dispersive Xray spectroscopy, transmission electron microscope, cyclic voltammetry, electrochemical impedance spectroscopy, and charge/discharge measurement were conducted to evaluate the physical and electrochemical properties of the CoO/3D graphene composite. Results showed that the composite delivered high rate capacities of 1481.1, 657.7, 472.5, 423.8, and 391.2 mAh g(-1), at 50, 100, 200, 300, 400, and 500 mA g(-1), respectively. The capacity after 100 cycles was 860 mAh g(-1) at 50 mA g(-1), thereby indicating excellent cycle stability. The excellent electrochemical performance was ascribed to 3D graphene sheets that were formed in the composite structure. (C) 2015 Elsevier B.V. All rights reserved.