High performance of mesoporous γ-Fe 2 O 3 nanoparticle/Ketjen Black composite as anode material for lithium ion batteries

•A mesoporous γ-Fe2O3/KB composite was synthesized via solvothermal method.•KB was used as a carbon template to improve electrochemical performance of γ-Fe2O3.•3D network structure can relieve volume change and improve the ionic transport.•The composite exhibited an ultrahigh capacity and high rate performance.