材料期刊网

A dual functional CNTs@graphene/CNTs cathode for Li-Se battery was constructed by a CNTs@graphene network and a CNTs interlayer.CNTs were first integrated with graphene to form a three-dimensional (3D) framework and work together as a conductive matrix for Se confinement.The optimized composite cathode delivers a high initial capacity of 575 mAh.g-1 at 0.5 A.g-1 and good rate capacity with a retained capacity of 479 mAh.g-1 at 2.0 A.g-1 (73％ of the capacity at 0.2 A.g-1).CNTs were further served as an interlayer to confine the diffusion of polyselenides by constructing a thin CNTs layer outside the CNTs@graphene network.An improved initial capacity of 616 mAh.g-1 at 0.5 A.g-1 is achieved with a retained capacity of 538 mAh.g-1 after 80 cycles,indicating the effective dual function of CNTs in this novel cathode construction and great application potential for Li-Se battery.