Scanning atom probe study of carbon nanotubes and graphite nanofibers with hydrogen terminated defects
Graphite nanofibers (GNF) and multi-wall carbon nanotubes (MWCNT) are mass analyzed utilizing the unique capability of the scanning atom probe. Various clusters of carbon and hydrogen are detected from MWCNT. These are mostly H+, H2+, C+, CH3+ and C2H5+. Few cluster ions are detected for the mass rang of 100 - 300. The largest mass peak is C28H4+ with two satellite mass peaks. The abundance of the satellites well agrees with the expected abundance of 12C2713CH4 and 12C2613C2H4, 28% and 4%, respectively. No H+ mass peak was found for GNF but the significant number of the ions such as C2H5+, C3H7+ and C4H9+ are detected. These ions are detected at the beginning of the mass analysis. After the removal of the surface layer, the detection rate of the largest cluster, C23H2, increases. The proposed structure of the C28H4 cluster is a rectangle formed three rows by three rows of hexagonal cells and that of C23H2 is the triangularly arranged six hexagonal cells. Four carbon atoms of C28H4 and two carbon atoms of C23H2 clusters are terminated by hydrogen.
Journal of Physics Conference Series
- Pub Date:
- March 2008