Nearly Space-Filling Fractal Networks of Carbon Nanopores

Abstract

Small-angle x-ray scattering, nitrogen adsorption, and scanning tunneling microscopy show that a series of activated carbons host an extended fractal network of channels with dimension $D_p=2.8\mathrm{}–3.0$ (pore fractal), channel width $15–20Å$ (lower end of scaling), network diameter $3000–3400Å$ (upper end of scaling), and porosity of 0.3–0.6. We interpret the network as a stack of quasiplanar invasion percolation clusters, formed by oxidative removal of walls between closed voids of diameter of $\sim 10Å$ and held in registry by fibrils of the biological precursor, and point out unique applications.