Titanium Oxide Filled Carbon Fibres for Lihium and Sodium Ion Insertion

Abstract

In this contribution, we would like to present structural and electrochemical characterization of composite carbon/TiO2 fibers prepared by centrifugal force spinning. Monoclinic TiO2-B is a very promising material with respect to lithium-ion insertion and unlike other TiO2 allotropes, TiO2-B crystallizes in monoclinic lattice with opened layered structure giving it extraordinary possibilities for lithium ion storage. Carbon fibers filled with TiO2 particles were prepared using PAN as carbon source together with the mixture of sodium trititanate Na2Ti3O7 and sodium hexatitanate Na2Ti6O13 as TiO2 source. The solution for preparation of fibers was made by dissolving PAN in DMF with dispersed hydrothermally synthesized Na2Ti3O7/Na2Ti6O13 nanorods. Fiberio Cyclone 1000M/D was used to spin the as prepared solution in the form of composite polymer/ceramic fibers which were heat treated in nitrogen atmosphere at 800°C subsequently. XRD measurements revealed that the sodium titanates were successfully transformed in the form of TiO2 with either monoclinic or tetragonal lattice. Electrochemical measurements were performed in aprotic electrolyte against metallic lithium in a three electrode setup. Cyclic voltammetry shows response typical for mixture of two crystallographic phases of TiO2 where TiO2-B is present. Figure 1