Gas Sensing Properties of Carbon Nanotubes Decorated with Iridium Oxide Nanoparticles

Abstract

The properties of Iridium oxide (IrO2) decorated Multi-Wall Carbon Nanotubes (IrO2-MWCNTs) are studied for detecting nitrogen dioxide and ammonia vapors. IrO2 nanoparticles were synthetized using a hydrolysis and acid condensation growth mechanism, and subsequently employed for decorating the sidewalls of carbon nanotubes. Decorated MWCNTs films were deposited onto SiO2/Si substrates for achieving chemoresistive gas sensors. NO2 and NH3 gases were detected under different experimental conditions. Higher and more stable responses towards NH3 and NO2 were observed for iridium-oxide nanoparticle decorated MWCNT material, compared to bare MWCNT material. Raman Spectroscopy was employed to study the nanomaterials and the optimal operating temperatures were determined.

Keywords

• carbon nanotubes
• iridium oxide
• metal nanoparticles
• gas sensing