Carbonization of ferrocene containing polymers and their electrochemical properties Original Research Article

Two iron-carbon composites were prepared from ferrocene-polymer mixtures with resol resin (Fe-RESOL) or epoxy resin (Fe-EPOXY), and they were compared with the previous composite (Fe-PFA) made from a ferrocene-poly(furfuryl alcohol) mixture from structural and the electrochemical viewpoints. The features of the composites were divided into two groups, that is, a group consists of Fe-PFA and Fe-RESOL and another of Fe-EPOXY. The (002) diffraction by X-ray diffraction of Fe-PFA and Fe-RESOL commonly showed defined peaks at ca 2θ = 26 ° which is characteristic to turbostratic structure, while only amorphous peak was observed for Fe-EPOXY. The electron microscopic studies revealed that both Fe-PFA and Fe-RESOL have fur-like surfaces by scanning electron microscopy and round-shaped crystalline by transmission electron microscopy, in contrast to the characteristics of Fe-EPOXY showing typical features to glass-like carbons. The electrochemical properties of the iron-carbon composites as working electrodes were studied by using cyclicvoltammetry of ferricyanide. Fe-RESOL showed narrow peak potential separation in the voltammogram as found for Fe-PFA previously, indicating the fast electron transfer at the surfaces of the electrodes, while Fe-EPOXY showed only a narrow voltammogram. It was inferred that turbostratic structure would be responsible for the higher electron transfer rate found for Fe-PFA and Fe-RESOL.