Carbon membranes of controlled thickness from colloidal crystals

Macroporous, free-standing carbon thin films with a perfectly defined number of pore layers are shown to be obtainable by applying a chemical vapor infiltration process to a colloidal crystal template. Raman spectroscopy indicates that the deposited carbon is partially graphitizable, and the usefulness of these membranes as electrodes is demonstrated. The membrane in the figure is approximately 4.3 mu m thick.