Catalytic graphitization by iron of isotropic carbon from polyfurfuryl alcohol, 725–1090 K. A high resolution electron microscope study

Abstract Iron as ferrocene was added to furfuryl alcohol. The doped monomer was polymerized to polyfurfuryl alcohol which was carbonized to heat treatment temperatures of 725–1090 K. Thin sections of these carbons were examined by high resolution electron microscopy to reveal the stacking arrangements of the constituent layers and the state of dispersion of the iron added as ferrocene. In the polyfurfuryl alcohol it was not possible to detect any aggregates of iron. However, small aggregates, ~5 nm, appear at 725 K and are distinct at 943 K. Significant catatylic graphitization by iron particles occurs at the relatively low temperature of 875 K (600°C) to produce a turbostratic graphite. Small aggregates of iron, ~20 nm diameter, are responsible for this form of graphitization, the particles having mobility or remaining stationary within the carbon matrix. An activation energy of 400 kJ mol−1 is derived for this form of graphitization.