Preparation and Electrochemical Properties of SnO2 Nanowires for Application in Lithium-Ion Batteries
One-dimensional (1D) nanostructured materials have received considerable attention for advanced functional systems as well as extensive applications owing to their attractive electronic, optical, and thermal properties.[1–2] In lithium-ion-battery science, recent research has focused on nanoscale electrode materials to improve electrochemical performance. The high surface-to-volume ratio and excellent surface activities of 1D nanostructured materials have stimulated great interest in their development for the next generation of power sources.[3–4] Materials based on tin oxide have been proposed as alternative anode materials with high-energy densities and stable capacity retention in lithium-ion batteries.[5–7] Various SnO2-based materials have displayed extraordinary electrochemical behavior such that the initial irreversible capacity induced by Li2O formation and the abrupt capacity fading caused by volume variation could be effectively reduced when in nanoscale form.[8–10] From this point of view, SnO2 nanowires can also be suggested as a promising anode material because the nanowire structure is of special interest with predictions of unique electronic and structural properties. Furthermore, the nanowires can be easily synthesized by a thermal evaporation method. However, in its current form, this method of manufacture of SnO2 nanowires has several limitations: it is inappropriate for mass production as high synthesis temperatures are required and there are difficulties in the elimination of metal catalysts that could act as impurities or defects. This results in reversible capacity loss or poor cyclic performance during electrochemical reactions.[ 11, 12] The critical issues relating to SnO2 nanowires as anode materials for lithium-ion batteries are how to avoid the deteriorative effects of catalysts and how to increase production.