title: Gas sensing at the nanoscale: engineering SWCNT-ITO nano-heterojunctions for the selective detection of NH3and NO2target molecules.
abstract: The gas response of single-wall carbon nanotubes (SWCNT) functionalized with indium tin oxide (ITO) nanoparticles (NP) has been studied at room temperature and an enhanced sensitivity to ammonia and nitrogen dioxide is demonstrated. The higher sensitivity in the functionalized sample is related to the creation of nano-heterojunctions at the interface between SWCNT bundles and ITO NP. Furthermore, the different response of the two devices upon NO2exposure provides a way to enhance also the selectivity. This behavior is rationalized by considering a gas sensing mechanism based on the build-up of space-charge layers at the junctions. Finally, full recovery of the signal after exposure to NO2is achieved by UV irradiation for the functionalized sample, where the ITO NP can play a role to hinder the poisoning effects on SWCNT due to NO2chemisorption.
authors.affiliation: Interdisciplinary Laboratory for Advanced Materials Physics and Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, via dei Musei 41 I-25121 Brescia, Italy. Sensor Lab, Department of Information Engineering, University of Brescia & CNR-INO, Brescia-Italy.
authors.forename: F
authors.initials: F
authors.lastname: Rigoni
authors.forename: G
authors.initials: G
authors.lastname: Drera
authors.forename: S
authors.initials: S
authors.lastname: Pagliara
authors.forename: E
authors.initials: E
authors.lastname: Perghem
authors.forename: C
authors.initials: C
authors.lastname: Pintossi
authors.forename: A
authors.initials: A
authors.lastname: Goldoni
authors.forename: L
authors.initials: L
authors.lastname: Sangaletti