Highly sensitive, transparent, and flexible gas sensors based on gold nanoparticle decorated carbon nanotubes

We report on a high performance flexible and transparent chemical sensor based on functionalised single-walled carbon nanotubes (SWCNTs). The SWCNT films were spray-deposited on transparent and flexible plastic substrates, and subsequently decorated with Au nanoparticles (AuNPs) providing a facile and cheap fabrication route. The electrical resistance of the films changed remarkably upon exposure to ammonia (NH3), AuNP decoration enhanced sensitivity to 255 ppb (parts-per-billion), one of the lowest reported so far. The reported sensor performance is a huge improvement towards low power consumption and its room temperature operation augers well for use in mobile devices for environmental protection and air quality control.