Graphene foam supported V2O5/N-C core/shell arrays as advanced cathode for lithium ion storage

It is an eternal goal to pursue high-performance electrode materials with both high energy & power densities. Herein we report lightweight bind-free positive electrodes by combing V2O5/N-doped carbon (N-C) core/shell arrays and graphene foam (GF) via solvothermal and self-polymerization methods. Active multileveled V2O5 nanoflakes with thicknesses of 10 nm are intimately wrapped by ultrathin N-doped carbon layer of similar to 2 nm forming core/shell arrays on the GF skeleton. Such an integrated electrode not only possesses merits of porous nanostructures with short ion/electron diffusion paths, but also shows improved structural stability and omni-bearing charge transfer ways for V2O5. As cathode of lithium ion batteries (LIBs), the GF+V2O5/N-C core/shell arrays exhibit superior Li ion storage properties with a noticeable initial capacity of 293 mAh g(-1) at 1C in the voltage range of 2.0-4.0 V and 223 mAh g(-1) at 5 C after 1000 cycles, better than the GF+V2O5 nanoflake counterpart. It is prospected that such integrated electrode design strategy can also be extended to fabricate other advanced positive electrodes for applications in energy storage. (C) 2017 Elsevier B.V. All rights reserved.