Effects of Ferrocene on Production of High Performance Carbon Electrodes from Poly(furfuryl alcohol)

The properties and structure of mixtures of ferrocene and poly(furfuryl alcohol) (PFA) were studied on carbonizing it at different temperatures up to 800 °C. Samples carbonized above 700 °C showed high heterogeneous electron transfer rates comparable to that of a platinum electrode, when these were used as working electrodes in cyclicvoltammetric studies of ferricyanide. Furlike structure was observed under SEM for these carbonized mixtures and the high electrochemical activity attributed to this structure. Mössbauer spectroscopy revealed that the introduced ferrocene had decomposed by 300 °C and was initially converted to magnetite, then to wustite, and finally to a mixture of α- and γ-iron and cementite. The electrical conductivity of the carbonized, iron-containing mixture was higher than that of the carbonized pure PFA by 1 order of magnitude for all the heat treatment temperatures investigated. The conductivity changed from an activated mechanism to metallic type at 700 °C heat treatment temperature. The major role of the introduced iron was considered to be to dissolve carbon atoms during heat treatment and then to deposit the filamentary carbon on cooling.