초록 |
The carbon nanotubes (CNTs) branched on three-dimensional (3D) macroporous, nitrogen-incorporated reduced graphene oxide (NG)/iron oxide (CNT/NG-Fe) hybrid architectures have been prepared via an ice templating and microwave synthesis. Compared with the pristine RGO, the CNTs can be more readily and uniformly grown on the 3D NG surfaces due to the good electronic conductivity by N-type configurations. As demonstrated by the electrochemical performances, the discharge capacity of the 3D CNT/NG-Fe is 1208 mAh g-1 at 50 mA g-1 which is greater than 890 and 820 mAh g-1 of the CNT/G-Fe and NG. After 130 cycles at 100 mA g-1, the capacity gradually increases to 1020 mAh g-1 with the Coulombic efficiency of > 98.5 %. The enhanced capacity, rate capability and cyclic stability of the CNT/NG-Fe are associated with the doping effect of N-configuration and unique hierarchical structure consisting of the dense CNT branches on 3D macroporous continuity. |