Selective and uniform growth of single-wall carbon nanotubes (SWCNTs) for gas sensing application

In the present work, we have synthesized uniformly distributed single-wall carbon nanotube (SWCNT) networks with a selective diameter suitable for gas sensing device. The SWCNT networks have been synthesized on 2-nm-thick iron (Fe) catalyst-coated silicon (Si) substrates by Plasma-Enhanced Chemical Vapor Deposition (PECVD). The as-grown SWCNTs were characterized by field emission scanning electron microscopy, high-resolution transmission electron microscopy, and Raman spectroscopy techniques. Using SWCNT network, the sensitivity of ammonia (NH 3 ) gases/vapors was recognized by their surface adsorption and desorption responses. The response curve was observed from the SWCNT network, which is due to a change in the resistance upon exposure to NH 3 gas.