Synthesis of high quality nitrogen-doped single-wall carbon nanotubes

Nitrogen-doped single-wall carbon nanotubes (SWCNTs) with diameters in the range of 1.1-1.6 nm were synthesized on a large scale by floating catalyst chemical vapor deposition. Ferrocene, methane and melamine were respectively used as the catalyst precursor, carbon source and nitrogen source. The content of nitrogen introduced into the SWCNT lattice was characterized to be similar to 0.4 at.%. This resulted in a decreased mean diameter, narrower tube diameter distribution, and increased surface area of the SWCNTs. The temperatures at which the rate of weight loss reaches the maximum value for N-SWCNTs are similar to 785 degrees C, similar to that of pure SWCNTs, indicative of their high-quality and good crystallinity. These N-SWCNTs exhibited a metallic behavior and desirable electrochemical oxygen reduction reaction activity.