Flower-like ZnO-NiO-C films with high reversible capacity and rate capability for lithium-ion batteries

Flower-like ZnO-NiO-C films with high reversible capacity and rate capability for lithium-ion batteries were fabricated through simple solution-immersion steps and subsequent heat treatment at moderate temperature. At a rate of 0.5 C, reversible capacity greater than 485 mAh g(-1) could be retained at the 50th cycle for ZnO-NiO-C films. More importantly, the films delivered reversible capacities of 380, 300, 230, and 180 mAh g(-1) at 1, 2, 3 and 4 C rates, respectively. The superior electrochemical properties of the ZnO-NiO-C films resulted from the advantages of flower-like architecture as well as the catalytic and conductive effects of the Ni phase produced in the first discharge process. Owing to easy fabrication and excellent electrochemical performance, these ZnO-NiO-C films will be promising anodes for lithium-ion batteries. The results of this study also offer possibilities of improving the lithium storage capacity of transition metal oxides by controlling both architecture and composition. (C) 2010 Elsevier Ltd. All rights reserved.