Three-dimensional-network Fe3O4/graphene/carbon nanotubes composite with high rate cycling capability as anode materials for lithium-ion batteries

Abstract

Fe3O4/graphene/carbon nanotubes composite was successfully synthesized through a facile solvothermal process. The Fe3O4 particles are dispersed in the three-dimensional (3D) conductive network forming by graphene nanosheets and cross-linked CNTs. As anode materials for lithium-ion batteries, the adding ratio of GO and CNTs in solvothermal process influences the electrochemical performance of the products. The obtained composite by the adding ratio of GO and CNTs 1:1 displays good electrochemical performance. The composite shows an initial charge capacity of 1244.9 and 1012.1 mA·h·g-1 after 200 cycles at a current density of 500mA·g-1. At the current density of 1300mA·g-1, it delivers 710.2 mA.h.g-1 after 200 cycles, remaining the initial charge capacity of 90.8%. In addition, the composite shows good coulomb efficiency and rate performance. The good performance of composite is described to the uniform distribution of Fe3O4 particles, graphene and CNTs in the 3D conductive network structure, which is beneficial for the electrolyte penetrating into the composite in all directions.