A High-Performance Anode Material for Li-Ion Batteries Based on a Vertically Aligned CNTs/NiCo2O4 Core/Shell Structure

3D vertically aligned carbon nanotubes (CNTs)/NiCo2O4 core/shell structures are successfully synthesized as binder-free anode materials for Li-ion batteries (LIBs) via a facile electrochemical deposition method followed by subsequent annealing in air. The vertically aligned CNTs/NiCo2O4 core/shell structures are used as binder-free anode materials for LIBs and exhibit high and stable reversible capacity (1147.6 mAhg(-1) at 100 mAg(-1)), excellent rate capability (712.9 mAh g(-1) at 1000 mAg(-1)), and good cycle stability (no capacity fading over 200 cycles). The improved performance of these LIBs is attributed to the unique 3D vertically aligned CNTs/NiCo2O4 core/shell structures, which support high electron conductivity, fast ion/electron transport in the electrode and at the electrolyte/electrode interface, and accommodate the volume change during cycling. Furthermore, the synthetic strategy presented can be easily extended to fabricate other metal oxides with a controlled core/shell structure, which may be a promising electrode material for high-performance LIBs.