Cu-Si1−xGex core-shell nanowire arrays as three-dimensional electrodes for high-rate capability lithium-ion batteries

► SiGe layer was deposited on the Cu nanowire arrays via a co-sputtering method. ► The Cu-SiGe 3D electrodes show improved performance as anode for Li-ion battery. ► Improved performance was attributed to the advantages of the electrodes' structure.