Template Free Electrodeposition of ZnSb Nanotube Array Electrodes for Li-Ion Batteries

S. Saadata, Q. Yan
Nanyang Technological University, SG

Keywords: electrochemical deposition, Li-ion battery, zinc antimony, nanotubes

Summary:

Electrodeposition is an effective synthesis process for the fabrication of nanostructured materials. Herein, we report a template free, single-step electrodeposition process to prepare ZnSb nanotubes with adjustable morphology under controlled over-potential conditions. Vertically aligned arrays of close-end ZnSb nanotubes were grown on ITO glass from an ethylene glycol solution under high over-potential conditions, while application of low over-potential deposition led to the formation of ZnSb nanoparticles. The growth of the ZnSb nanotubes is believed to be due to the dynamic template effect of H2 bubbles generated under such over-potential conditions. For electrochemical evaluation of ZnSb nanotubes, CNT was successfully added as conducting agent. The electrochemical tests showed that the ZnSb nanotubes exhibited an initial discharge capacity of 637 mA h/g and a low irreversible capacity loss (ICL) of 10% and maintained a discharge capacity of 400 mA h/g after 100 cycles. Additionally, the ZnSb nanotubes depicted superior rate capabilities compared to ZnSb nanoparticles. The improved Li storage performance of the ZnSb nanotubes is mainly attributed to their hollow and one dimensional nanostructure, which can facilitate the Li ion diffusion and buffer the strain induced during the lithiation process.