Synthesis, Characterization And Applications Of Nitrogen-doped Micro/Nano-sized Carbon Materials

Carbon based micro/nano-sized materials, including carbon nanotubes (CNTs), carbon microtubes (CMTs), have potential applications in various fields, such as energy storage and field emission display due to their unique chemical and electrical properties. Theoretical and experimental results demonstrate that doping carbon with nitrogen can tailor the crystal and electronic structure of carbon materials. However, the synthesis of nitrogen doped micro/nano carbon materials in large-scale is still a challenge.In the present work, we prepared nitrogen doped carbon nanotubes (N-CNTs) filled with iron, nitrogen doped carbon microtubes (N-CMTs) and carbon nitrides via floating catalyst chemical vapor deposition (CVD) and pyrolysis method. Finally, the applications of these as-prepared nitrogen doped micro/nano carbon materials have been investigated. The major results are briefly summarized as follows.N-CMTs with net-like structures have been synthesized using anhydrous ferric chloride as a catalyst precursor and melamine as both carbon and nitrogen sources by means of a floating catalyst CVD method. The N-CMTs from our floating catalyst method have a diameter of0.5-1urn, and the products exhibit stable performance as supercapacitor materials.N-CNTs filled with iron have been synthesized using anhydrous ferric chloride as a catalyst precursor and melamine as both carbon and nitrogen sources by means of a floating catalyst CVD method. It is noteworthy that the N-CNTs with an outer diameter of250nm exhibit an irregular and corrugated morphology due to the nitrogen incorporation. The products exhibit potential applications in magnetic data storage devices, field emission display and electromagnetic wave adsorption. Finally, annealing treatment and air oxidation were applied on the products respectively in order to investigate the conversion of iron in the N-CNTs.Graphitic carbon nitrides/graphene composites have been successfully synthesized via a high pressure and high temperature pyrolysis route using melamine and graphite oxide as starting materials. The composites exhibit potential application in supercapacitors.