Micro and mesoporosity of carbon derived from ternary and binary metal carbides

In this work we systematically characterized both the micro- and mesoporosity that develops when Ti3SiC2, Ti3AlC2, Ti2AlC, Ti2AlC0.5N0.5, Ta2AlC, Ta2C, and TaC are chlorinated at different temperatures. The porosity of the carbide-derived carbon varied based on the initial carbide's structure and chemistry. The carbides with anisotropic structures, such as the layered ternary carbides, result in larger mesopore volumes as compared to more isotropic carbides such as TaC. Furthermore, the carbon pore structure can collapse, resulting in low pore volumes for materials with low molar fractions of carbon, as was the case with Ti2AlC0.5N0.5. (C) 2007 Elsevier Inc. All rights reserved.