(48e) Preparation of Mesoporous Carbon/Silica Nanocomposites and Bimodal Carbon Particles by Aerosol-Assisted Self-Assembly

Hu, Q. - Presenter, General Motors R&D Center
Rong, K. - Presenter, Tulane University
Pang, J. - Presenter, Tulane University
Lu, Y. - Presenter, Tulane University
Ward, T. L. - Presenter, Univ of New Mexico

Silica and carbon play important roles in materials science due to their excellent physical and chemical properties and their widely applications. Several papers have reported the combinations of these two materials to fabricate carbon/silica hybrids because the combination of silica and carbon can potentially combine the advantages of each material to create a composite with improved surface properties, adsorption capabilities, chemical and hydrothermal stabilities. Carbon/silica composites have been successfully created through several methods, including coating of silica gel on the carbon surface through hydrolysis of a silica precursor, carbonization in porous silica channels and carbonization of benzene-containing bridge silane. However, the synthesis of ordered mesoporous carbon/silica nanocomposites with tunable carbon/silica ratio is still a challenge. In this report, an aerosol-based self-assembly approach were explored to synthesize mesoporous spherical polymer/silica, carbon/silica nanocomposites and bimodal carbon particles from precursor solutions containing carbonizable oligomers, silicate species and block co-polymer template. The resulted mesoporous carbon/silica spherical particles show ordered mesostructures with high porosity and narrow pore size distributions. The carbon/silica ratio can be easily controlled by changing the concentration of carbon precursor in precursor solution without altering the ordered structures. The removal of silica part in the carbon/silica nanocomposites leads to the formation of highly porous bimodal mesoporous carbons with extreme high surface areas. The large pores are templated by the block copolymer and the small pores are templated by the silica frameworks. The surface areas of the bimodal carbons can reach as high as 2000 m2/g. These spherical porous carbon/silica nanocomposites particles and bimodal mesoporous carbon particles may have potential applications such as catalysts supports, column packing adsorbents, nanocomposite fillers, hydrogen storage, and supercapacitors.