title: Aerosol-assisted CVD-grown WO₃ nanoneedles decorated with copper oxide nanoparticles for the selective and humidity-resilient detection of H₂S.
abstract: A gas-sensitive hybrid material consisting of Cu2O nanoparticle-decorated WO3 nanoneedles is successfully grown for the first time in a single step via aerosol-assisted chemical vapor deposition. Morphological, structural, and composition analyses show that our method is effective for growing single-crystalline, n-type WO3 nanoneedles decorated with p-type Cu2O nanoparticles at moderate temperatures (i.e., 380 °C), with cost effectiveness and short fabrication times, directly onto microhot plate transducer arrays with the view of obtaining gas sensors. The gas-sensing studies performed show that this hybrid nanomaterial has excellent sensitivity and selectivity to hydrogen sulfide (7-fold increase in response compared with that of pristine WO3 nanoneedles) and a low detection limit (below 300 ppb of H2S), together with unprecedented fast response times (2 s) and high immunity to changes in the background humidity. These superior properties arise because of the multiple p-n heterojunctions created at the nanoscale in our hybrid nanomaterial.
authors.affiliation: †Research Centre on the Engineering of Materials and micro/nano Systems, Universitat Rovira i Virgili Països Catalans 26, 43007 Tarragona, Spain.
authors.forename: Fatima E
authors.initials: FE
authors.lastname: Annanouch
authors.affiliation: †Research Centre on the Engineering of Materials and micro/nano Systems, Universitat Rovira i Virgili Països Catalans 26, 43007 Tarragona, Spain.
authors.forename: Zouhair
authors.initials: Z
authors.lastname: Haddi
authors.affiliation: ‡SIX Research Center, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technicka 12, CZ-61600 Brno, Czech Republic.|§̂Instituto de Microelectrónica de Barcelona, Consejo Superior de Investigaciones Científicas, Campus UAB, 08193 Bellaterra, Barcelona, Spain.
authors.forename: Stella
authors.initials: S
authors.lastname: Vallejos
authors.affiliation: ⊥Solid State, Physics Department, Jožef Stefan Institute, 39 Jamova cesta, 1000 Ljubljana, Slovenia.
authors.forename: Polona
authors.initials: P
authors.lastname: Umek
authors.affiliation: ∥Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Institute for Soft Matter and Functional Materials, Albert-Einstein-Strasse 15, 12489 Berlin, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Guttmann
authors.affiliation: #Plasma-Surface Interaction Chemistry University of Mons, 1 Copernic, 7000 Mons, Belgium.
authors.forename: Carla
authors.initials: C
authors.lastname: Bittencourt
authors.affiliation: †Research Centre on the Engineering of Materials and micro/nano Systems, Universitat Rovira i Virgili Països Catalans 26, 43007 Tarragona, Spain.
authors.forename: Eduard
authors.initials: E
authors.lastname: Llobet
keywords: aerosol-assisted CVD; functionalization; gas sensor; nanoneedles; nanoparticles