SAXS chord length distribution analysis and porosity estimation of activated and non-activated glassy carbon

The porosity of activated and non-activated glassy carbon was studied by small-angle X-ray scattering. Based on first geometric principles (Rosiwal’s linear integration principle, isotropic uniform random chord length distributions), the porosities have been obtained, in contrast to more conventional techniques, by means of the second derivative of the small-angle scattering correlation function γ(r). Estimates of the porosity p are based on the range order L=2.5 nm, which corresponds to a sequence pore/wall/pore by means of a so-called linear simulation model. Specific assumptions about size, shape, pore topology, pore accessibility, and pore blocking effects are not required.