Electrochemical lithium insertion into a poly(3,4-ethylenedioxythiophene) PEDOT/V₂ O₅ nanocomposite

Abstract

A nanocomposite comprised of conductive poly(3,4-ethylene dioxythiophene)PEDOT chains interleaved between the layers of crystalline V₂O₅ powder has been synthesized by direct in situ oxidation. The interlayer spacing of V₂O₅ expands from 4.32 to 13.84 Å and this interlayer separation is consistent with the existence of a monolayer of PEDOT in the V₂O₅ framework. The nanocomposite is coupled with a large-area Li foil counter electrode and a Li wire reference electrode in 1 M LiClO₄ in a mixture of ethylene and dimethylcorbonate (50/50 by volume), the discharge capacity is ≥ 300 m Ah g^-1 which is larger than that of pristine V₂O₅. The significant difference in capacity is explained on the basis of lithium ions insertion/de-insertion between the layers of V₂O₅.