Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Carbon nanotubes and carbon nanofibers fabricated on tubular porous Al2O3 substrates

: Simon, Adrian; Seyring, M.; Kämnitz, Susanne; Richter, Hannes; Voigt, Ingolf; Rettenmayr, M.; Ritter, U.


Carbon 90 (2015), S.25-33
ISSN: 0008-6223
Fraunhofer IKTS ()

Carbon nanotubes and carbon nanofibers were grown at different temperatures on porous ceramic Al2O3 substrates with single channel geometry by means of a chemical vapor deposition technique using methane as carbon source and palladium as catalyst. Time-resolved in-situ Fourier transformed infrared spectroscopy was used for the investigation of methane decomposition for characterizing the catalyst’s performance. With increasing synthesis temperature, a structural transition from carbon nanofibers to carbon nanotubes was observed. At a synthesis temperature of 700 °C, solely carbon nanofibers were found, whereas at 800 °C a mixture of two types of bamboo-shaped carbon nanofibers were obtained, suggesting a structural transition. A synthesis temperature to 850 °C results in bamboo-shaped multi-walled carbon nanofibers and multi-walled carbon nanotubes. The carbon products and the observed structural transition were characterized by means of field emission scanning electron microscopy, high-resolution transmission electron microscopy, thermal gravimetric analysis, and Raman spectroscopy.