Interpenetrating Phenolic/Oxide Networks And Carbothermal Synthesis Of Metallic And Carbide Aerogels

Aerogels, xerogels, and polymer-crosslinked aerogels consisting of interpenetrating networks of phenolic resin/oxide nanoparticles are synthesized in one pot through the catalytic effect of gelling solutions of hydrated metal ions on the gelation of phenolic resins. Pyrolysis under Ar induces carbothermal reduction, which, depending on the chemical identity of the oxide, yields either metals in the element form or the corresponding carbides. RF-MOx networks in the xerogel and polymer-crosslinked aerogel (X-aerogel) forms undergo carbothermal reduction at as much as 400 °C lower temperatures than in the native aerogel form, pointing to the importance of compactness in the reactions of nanostructured matter. The carbothermal reduction of interpenetrating networks is useful for the synthesis of nanoporous monolithic metals and carbides. Certain such nanostructured metals may find applications as energetic materials (pyrotechnics, explosives, thermites).