Porous CuO nanotubes/graphene with sandwich architecture as high-performance anodes for lithium-ion batteries.

Constructing a porous conductive framework represents a promising strategy for designing high-performance anodes for Li-ion batteries. Here, porous CuO nanotubes/graphene with hierarchical architectures were fabricated by simple annealing of copper nanowires/graphene hybrids synthesized by a microwave-assisted process. In these nanoarchitectures, the embedded porous CuO nanotubes can prevent restacking of the graphene sheets, whereas graphene can increase the electrical conductivity of CuO. Moreover, these two components constitute a sandwich-like interlaced framework that favors ion diffusion, as well as promoting better electron transport. As a result, the as-prepared nanohybrid exhibits a high specific capacity of 725 mA h g-1 and a capacity retention of ∼81% after 250 cycles, as well as outstanding rate performance in comparison to those of bare CuO or a CuO-CNT (carbon nanotubes) hybrid.