Three-dimensional copper oxide structures composed of single crystal nanosheets have been successfully prepared by a green electrochemical alternating voltage approach. This special structure of copper oxide grown along the [010] direction can be effective to accommodate the volume expansion during charge-discharge cycles. The obtained product as anode materials in lithium-ion batteries displays outstanding electrochemical performances with a high reversible capacity of 635.2 mA h g(-1) after 50 cycles at 100 mA g(-1) close to the theoretical capacity of copper oxide (674 mA h g(-1)). (C) 2016 Elsevier B.V. All rights reserved.