Heterogeneous\nTiO₂/V₂O₅/Carbon Nanotube Electrodes\nfor Lithium-Ion Batteries

Abstract

Vanadium\npentoxide (V₂O₅) is proposed and investigated\nas a cathode material for lithium-ion (Li-ion) batteries. However,\nthe dissolution of V₂O₅ during the charge/discharge\nremains as an issue at the V₂O₅–electrolyte\ninterface. In this work, we present a heterogeneous nanostructure\nwith carbon nanotubes supported V₂O₅/titanium\ndioxide (TiO₂) multilayers as electrodes for thin-film\nLi-ion batteries. Atomic layer deposition of V₂O₅ on carbon nanotubes provides enhanced Li storage capacity and high\nrate performance. An additional TiO₂ layer leads to increased\nmorphological stability and in return higher electrochemical cycling\nperformance of V₂O₅/carbon nanotubes. The physical\nand chemical properties of TiO₂/V₂O₅/carbon nanotubes are characterized by cyclic voltammetry and charge/discharge\nmeasurements as well as electron microscopy. The detailed mechanism\nof the protective TiO₂ layer to improve the electrochemical\ncycling stability of the V₂O₅ is unveiled.