Gas sensing at the nanoscale: engineering SWCNT-ITO nano-heterojunctions for the selective detection of NH3 and NO2 target molecules
Authors: Rigoni F., Drera G., Pagliara S., Perghem E., Pintossi C., Goldoni A., Sangaletti L.
Autors Affiliation: Univ Cattolica Sacro Cuore, Interdisciplinary Lab Adv Mat Phys, Via Musei 41, I-25121 Brescia, Italy; Univ Cattolica Sacro Cuore, Dipartimento Matemat & Fis, Via Musei 41, I-25121 Brescia, Italy; Univ Brescia, Sensor Lab, Dept Informat Engn, Brescia, Italy; CNR, INO, Brescia, Italy; Elettra Sincrotrone Trieste SCpA, Ss 14 Km 163-5, I-34149 Trieste, Italy
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 NO2 exposure 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 NO2 is 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 NO2 chemisorption.
Volume: 28 (3) Pages from: 035502-1 to: 035502-10
KeyWords: heterojunction; nano-heterojunction; carbon nanotubes; indium tin oxide nanoparticles; ITO nanoparticles; gas sensing; ammonia gas sensingDOI: 10.1088/1361-6528/28/3/035502Citations: 12data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2021-10-24References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here