Synthesis of nanocomposite powders of γ-alumina-carbon nanotube by sol–gel method

The nanocomposite powders of γ-alumina-carbon nanotube were successfully synthesized by a sol–gel process. The homogeneous mixture of carbon nanotubes and alumina particles was obtained by mixing the carbon nanotubes within alumina solution and followed by heating into gel. The resultant gel was dried and calcined at 200 °C into boehmite-carbon nanotubes composite powders. The mean particle size of synthesized boehmite was of the order of 4 nm. The boehmite-carbon nanotubes composite powders were calcined at different temperatures and XRD investigations revealed that as the amount of carbon nanotube increases, γ- to α-alumina phase transformation is completed at higher temperatures. The specific surface area and mean particle size of resultant nanocomposite powders increased and decreased, respectively by increasing the content of carbon nanotubes.