Carbon black anchored vanadium oxide nanobelts and their post-sintering counterpart (V2O5 nanobelts) as high performance cathode materials for lithium ion batteries

Abstract

Carbon black (CB) anchored vanadium oxide (C-VO_x) nanobelts are successfully prepared by a simple sol–gel route and subsequent hydrothermal treatment. The synthesized C-VO_x nanobelts display high specific capacity and good cycling stability as a cathode material for lithium ion batteries (LIBs) (232 mA h g⁻¹ at initial discharge and 195 mA h g⁻¹ during 50th discharge at a current density of 100 mA g⁻¹ between 1.5–4 V versus Li) due to the nano-belted morphology and closely attached CB. The orthorhombic V₂O₅ nanobelts can be obtained by post-sintering of C-VO_x nanobelts in air. These V₂O₅ nanobelts, which maintain their previous belted morphology and possess higher vanadium valence, exhibit superior electrochemical properties, especially the higher specific capacity (406 mA h g⁻¹ and 220 mA h g⁻¹ during the 1st and 50th discharge at a current density of 100 mA g⁻¹, and 146 mA h g⁻¹ at a current density of 1000 mA g⁻¹ between 1.5–4 V versus Li). Both of them can be used as high performance cathode materials for LIB application. Furthermore, a full-cell using V₂O₅ nanobelts as the cathode and lithiated graphite as the anode is assembled and its electrochemical performance is measured in the voltage range of 1.5–3.8 V.