Premium
Modelling the effects of nitrogen doping on the carbon nanofiber growth via catalytic plasma‐enhanced chemical vapour deposition process
Author(s) -
Gupta Ravi,
Sharma Suresh C.
Publication year - 2019
Publication title -
contributions to plasma physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.531
H-Index - 47
eISSN - 1521-3986
pISSN - 0863-1042
DOI - 10.1002/ctpp.201700138
Subject(s) - carbon nanofiber , materials science , chemical vapor deposition , plasma enhanced chemical vapor deposition , nitrogen , catalysis , chemical engineering , carbon fibers , field electron emission , plasma , doping , dissociation (chemistry) , analytical chemistry (journal) , nanotechnology , carbon nanotube , composite material , chemistry , electron , environmental chemistry , organic chemistry , physics , optoelectronics , quantum mechanics , composite number , engineering
An analytical model is developed to describe the effects of nitrogen doping on the growth of the carbon nanofibers (CNFs) and to elucidate the growth mechanism of nitrogen‐contained carbon nanofibers (N‐CNFs) on the catalyst substrate surface through the plasma‐enhanced chemical vapour deposition (PECVD) process. The analytical model accounts for the charging of CNFs, kinetics of all plasma species (electrons, ions, and neutrals) in the reactive plasma, generation of carbon species on the catalyst nanoparticle surface due to dissociation of hydrocarbons, CNF growth due to diffusion and precipitation of carbon species, and various other processes. First‐order differential equations have been solved for glow discharge plasma parameters for undoped CNFs (CNF growth in C 2 H 2 /H 2 plasma) and nitrogen‐doped CNFs (N‐CNF growth in C 2 H 2 /NH 3 plasma). Our investigation found that nitrogen‐doped CNFs exhibit lower tip diameters and smaller heights compared to the undoped CNFs. In addition, we have estimated that nitrogen‐doped CNFs have more enhanced field emission characteristics than the undoped CNFs. Moreover, we have also observed that N‐CNFs' growth rate increases and tip diameter decreases as the C 2 H 2 /NH 3 gas ratio decreases. The theoretical results of the present investigation are consistent with the existing experimental observations.