Nitrogen Doped Carbon Nanotubes from Organometallic Compounds: A Review

Abstract

Nitrogen doped carbon nanotubes (N-CNTs) have become a topic of increased importance in the study of carbonaceous materials. This arises from the physical and chemical properties that are created when N is embedded in a CNT. These properties include modified chemical reactivity and modified conductivity and mechanical properties. A range of methodologies have been devised to synthesize N-CNTs. One of the procedures uses a floating catalyst in which an organometallic complex is decomposed in the gas phase in the presence of a nitrogen containing reactant to give N-CNTs. Most studies have been limited to ferrocene, ring substituted ferrocene and Fe(CO)5. This review covers the synthesis (and properties) of N-CNTs and other shaped carbon nanomaterials (SCNMs) produced using organometallic complexes. It summarizes the effects that physical parameters such as temperature, pressure, gas flow rates, type and concentration of N source etc. have on the N-CNT type, size and yields as well as the nitrogen content incorporated into the tubes that are produced from organometallic complexes. Proposed growth models for N-CNT synthesis are also reported.

Biocomposite membranes based on poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and multiwall carbon nanotubes for gas separation

“…The CNT structure is characterized by a highly regular arrangement of carbon atoms leading to a high crystallinity. The Raman spectrum showed that the I G /I D decreased from 5.70 to 1.71 when the MWCNTs were doped with N; this result is in accordance with that previously reported for N-doped CNTs [18][19][20][31][32][33]. The decrease in I G /I D indicates a decrease in the crystallinity of carbonaceous structures, which, in this case, was due to the defects created by the N atoms.…”

“…The short f-MWCNTs could be beneficial for gas transportation through the inner cavities of the tubes because of CNTs with an increased number of open ends and a more uniform dispersion due to their decreased length. Nitrogen doping has been proven to be an effective method to tailor the electrical properties as well as the chemical reactivity of CNTs [15][16][17][18][19][20]. However, the use of N-doped CNTs for obtaining shortened nanotubes has not been reported thus far.…”

Controlling pyridinic, pyrrolic, graphitic, and molecular nitrogen in multi-wall carbon nanotubes using precursors with different N/C ratios in aerosol assisted chemical vapor deposition

“…It was shown that the concentration and the type of nitrogen depend on the synthesis temperature, gas flow rate, and nature of the catalyst as well as the type of nitrogen precursor. [14][15][16][17] The most common forms of embedded nitrogen discussed in the literature are graphitic, pyridinic and pyrrolic nitrogen. 1,[18][19][20] Graphitic nitrogen refers to a nitrogen atom with three carbon neighbours in a hexagonal lattice, if the nitrogen is two-fold coordinated similar to that is found in pyridine, it is called pyridinic, and three-fold coordinated nitrogen in a region of defective non-aromatic lattice is associated with pyrrolic nitrogen.…”

Nitrogenated Carbon Nanotubes: Methods of Fabrication, Properties, and Prospect of Application

“…ВНР з різним вмістом азоту (до 10%) було одержано методою хемі-чного парового осадження з використанням фероцену, NH 3 і ксилолу чи піридину як каталізаторів [20,21]. РФЕС-аналіза виявила зсув і розширення рівня C1s спектру зі збільшенням невпорядкованости, зумовленої селективним леґуванням азотом.…”