Fabrication and electrochemical behavior of flower-like ZnO-CoO-C nanowall arrays as anodes for lithium-ion batteries

This study reported the electrochemical performance of flower-like ZnO-CoO-C nanowall arrays as anodes of lithium-ion batteries. The arrays were fabricated through solution-immersion steps and subsequent calcination at 400 degrees C. At a rate of 0.5 C, the arrays exhibited a delithiation capacity of 438 mA h g(-1) at the 50th cycle. The arrays still delivered a reversible capacity of 224 mA h g(-1) at 2.0 C rate, much higher than those of the flower-like ZnO and ZnO-C nanowall arrays. The mechanism for the high capacity of flower-like ZnO-CoO-C nanowall arrays mainly resulted from the catalytic effect of Co phase on the decomposition of Li2O and the conducting carbon layer formed on ZnO nanowalls. The present finding also provides a kind of nanostructured films that might be applied in solar cells and sensors, etc. (C) 2011 Elsevier B. V. All rights reserved.