Preparation and characterization of ultrathin free-standing carbon films

Ultrathin free-standing carbon films with thicknesses of ∼8-14 nm were prepared by peeling from glass after pyrolization of the polyfurfuryl alcohol precursor at 700 °C. The carbon films were characterized by using optical profilometry, confocal Raman spectroscopy, transmission electron microscopy, UV-vis spectroscopy, and a two-point probe I - V station measurement. The results confirmed the formation of ultrathin free-standing carbon films with a polyaromatic domain structure. Those films had up to a 90% transmittance with respect to air and had an ohmic behavior. In this work, we also suggest that the most likely peeling mechanism of carbon films results from glass corrosion.