Synthesis Optimization and Characterization of Nitrogen-Doped Bamboo-Shaped Carbon Nanotubes

Nitrogen-doped bamboo-shaped carbon nanotubes (N-BCNT) were synthesized from butylamine using the catalytic chemical vapor deposition (CCVD) process. The carbon source was nitrogen content organic molecules, namely butylamine. Reaction conditions such as temperature, amount of carbon source and catalyst were optimized to produce high quality N-BCNT samples. The nitrogen content was measured by CHNS element analysis, while the butylamine conversion was calculated based on the weight of deposited carbon materials. The bamboo structure of the nanotubes was examined by high resolution transmission electron microscopy (HRTEM). Two different types of nitrogen incorporation forms, the pyridinic and the graphitic, were identified in the samples by X-ray photoelectron spectroscopy (XPS). The lattice defects were measured by Raman spectroscopy. The proportion of defect sites influenced by the nitrogen content which can be controlled by the synthesis temperature. The optimal conditions were identified for the economical synthesis of N-BCNTs with high nitrogen content for various applications.