Synthesis and characterization of copper-doped carbon aerogels

We have prepared carbon aerogels (CAs) doped with copper through sol-gel polymerization of formaldehyde with the potassium salt of 2, 4-dihydroxybenzoic acid, followed by ion exchange with Cu(NO3)(2), supercritical drying with liquid CO2, and carbonization at 1050 degreesC under a N-2 atmosphere. The materials were characterized by elemental analysis, nitrogen adsorption, high-resolution transmission electron microscopy, and X-ray diffraction. Results obtained indicate that this approach is an effective method for controlling both the amount and the distribution of a desired metal species within the carbon framework. We also found that carbonization of the copper-doped organic aerogels results in the formation of spherical copper nanoparticles within the carbon framework of the aerogel. The copper nanoparticles have a cubic crystalline structure and range in size from 10 to 50 nm. The Cu-doped CAs retain the overall open cell structure of metal-free CAs, exhibiting high surface areas and pore diameters in the micro- and mesoporic region.