Formation of graphitic carbon nanofiber (GCNF)/silica gel composites using surface-functionalized GCNFs and sol-gel processing

Reaction of herring-bone graphitic carbon nanofibers (GCNFs) containing surface-bound acid chloride functional groups with 3-aminopropyl triethoxysilane, (APTES) leads to amide condensation and formation of carbon nanofibers surface-derivatized with pendant Si-OEt and Si-OH functional groups. GCNF-[C(O)NH(CH2)(3)Si(OEt)(OH)(2)](x). Addition of these GCNFs containing covalently bound 3-amidopropylsilyl linker molecules to silica sol-gel formulations gives GCNF/silica xerogels as dry black powders. Covalent binding of the linker molecule across the GCNF/ceramic interface is indicated by intermediate formation of especially stable GCNF/silica sol dispersions and the isolation of uniformly black GCNF/silica xerogel powders. SEM micrographs reveal excellent wetting of the carbon nanofiber surface by the silica xerogel matrix. and the presence of amido-carbonyl groups is confirmed from infrared spectral data. TGA plots show mass losses consistent with dehydration of the get matrix and thermal decomposition of linker molecules at elevated temperature.