Gas Sensors Based on Deposited Single-Walled Carbon Nanotubes-Polypyrrole Networks for Ammonia Detection

Abstract

In this work, we demonstrate excellent gas sensors based on single-walled carbon nanotubes (SWNTs)-polypyrrole (PPy) networks for the detection of ammonia (NH3) gas. The SWNTs networks were deposited on oxidized silicon surface functionalized with 3-aminopropytrimethysilane. The Fe3+ions were easily adsorbed on the surface of SWNTs by ion exchange process. After deposition of PPy molecules on the surface of SWNTs by chemical vapor polymerization process in a sealed container with pyrrole vapors, SWNTs-PPy networks were formed. By the combination of traditional silicon processes, SWNTs-PPy networks-based gas sensors were fabricated at a wafer scale. The sensitive properties of the resultant gas sensors for the detection of NH3gas were investigated at room temperature. And the results suggested that the gas sensors based on SWNTs-PPy networks exhibited excellent sensitivity to NH3gas. This new method is very simple, which holds great potential in the wide spread practical production.