Letters in High Energy Physics (Feb 2024)
The Effect of Carbon Nanotubes on the Conductivity and Sensitivity Properties of Polypyrrole for the Detection of NO₂ Gas
Abstract
Composite films of polypyrrole (PPy) with multi-walled carbon nanotubes (MWCNTs) were prepared for nitrogen dioxide (NO₂) gas sensor application. The fabrication process was carried out using the chemical polymerization method of pyrrole monomer with FeCl₃ and the addition of MWCNTs in 50 mL of distilled water. Next, polypyrrole (PPy) and with multi-walled carbon nanotubes (MWCNTs (nanocomposites were deposited on glass substrates and an aluminum mask was applied to the composite thin disks. The nanocomposites were characterized by scanning electron microscopy (FE-SEM) and the electrical conductivity of the nanocomposites was measured at different temperatures (RT, 100, 200 °C). The results showed an improvement in conductivity when CNTs were added to polypyrrole. The response and recovery time of the composite films in the presence of NO₂ gas was calculated by monitoring the electrical resistance at temperatures (RT, 100, 200 °C). The sensitivity of the composites to gas was also calculated, observing that the PPy/MWCNTs nanocomposite films exhibited higher sensitivity compared to pure PPy. The results show that the incorporation of multiple carbon nanotubes significantly increases the electrical conductivity and sensitivity to NO₂, highlighting the possibility of using this compound in the development of efficient gas sensors.
