Facile synthesis of NaV6O15 nanorods and its electrochemical behavior as cathode material in rechargeable lithium batteries

Abstract

A ternary vanadium bronze compound, NaV₆O₁₅ (Na_0.33V₂O₅), constructed by highly ordered nanorod structures, was facilely synthesized via a low temperature hydrothermal route using V₂O₅, H₂O₂ and NaCl as the precursors. A reaction mechanism involved in present hydrothermal condition was tentatively proposed. The sample was systemically post-treated at different temperatures and well characterized by various techniques. It was found that the prepared NaV₆O₁₅ nanorods had a highly crystallined single phase with a preferred c* orientation growth. When used as the cathode material in rechargeable lithium batteries, the NaV₆O₁₅ nanorods exhibited stable lithium-ion insertion/deinsertion reversibility and delivered as high as 328 mAh g⁻¹ lithium cycled at the current density of 0.02 A g⁻¹. In galvanostatic cycling test, a specific discharge capacity of around 300 mAh g⁻¹ could be demonstrated for 70 cycles under 0.05 A g⁻¹ current density. According to its unique crystallographic structure and electrochemical characteristics, it is therefore expected that as-prepared NaV₆O₁₅ nanorods may be employed as cathode material in rechargeable lithium, sodium-based batteries.