Nanostructured Cu2O thin film electrodes prepared by electrodeposition for rechargeable lithium batteries

Uniform films of Cu2O with thickness below 1 μm were prepared from a Cu(II) lactate solution. The deposits were compact and of high purity with the particle size varying from 60 to 400 nm. They were tested as electrodes in lithium batteries and their electrochemical response was consistent with the Cu2O + 2e− + 2Li+ ↔ 2Cu + Li2O reaction. Nevertheless, the reversibility of this reaction was dependent on thickness. Kinetic factors associated with the poor electronic conductivity of Cu2O could account for the relevance of the influence of film thickness. The thinnest film, about 300 nm thick, exhibited the best electrochemical performance by sustaining a specific capacity as high as 350 Ah kg− 1.