A novel three-dimensional architecture of Co–Ge nanowires towards high-rate lithium and sodium storage

Abstract

We demonstrate the synthesis of Co–Ge three-dimensional nanowire arrays directly anchored on the current collector via the growth of Co nanowire arrays and subsequent RF-deposition of Ge. When used as anode materials for lithium-ion batteries, the Co–Ge nanowire arrays show a reversible capacity of 1535 mAh g−1 after 100 cycles at a current density of 320 mA g−1 and a capacity of 1239 mAh g−1 even at 8000 mA g−1. With respect to sodium-ion batteries, cycling capacity of ∼350mAh g−1 after 100 cycles is obtained. The excellent electrochemical properties may be attributed to the unique three-dimensional array nanostructures that can provide robust mechanical support, fast electron transport, and good strain accommodation.