摘要
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.
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.
基金
financially supported by the National Basic Research Program of China(No.2014CB932400)
the National Science Foundation of China(Nos.21406161 and 51602220)