Co-doped NiO nanoflake arrays toward superior anode materials for lithium ion batteries

摘要

Co-doped NiO nanoflake arrays with a cellular-like morphology are fabricated by low temperature chemical bath deposition. As anode material for lithium ion batteries (LIBs), the array film shows a capacity of 600mAhg~(-1) after 50 discharge/charge cycles at low current density of 100mAg~(-1), and it retains 471 mAhg"1 when the current density is increased to 2 Ag~(-1). Appropriate electrode configuration possesses some unique features, including high electrode-electrolyte contact area, direct contact between each naonflake and current collector, fast Li* diffusion. The Co~(2+) partially substitutes Ni~(3+), resulting in an increase of holes concentration, and therefore improved p-type conductivity, which is useful to reduce charge transfer resistance during the charge/discharge process. The synergetic effect of these two parts can account for the improved electrochemical performance.