title: Evaluation of gas-sensing properties of ZnO nanostructures electrochemically doped with Au nanophases.
abstract: A one-step electrochemical method based on sacrificial anode electrolysis (SAE) was used to deposit stabilized gold nanoparticles (Au NPs) directly on the surface of nanostructured ZnO powders, previously synthesized through a sol-gel process. The effect of thermal annealing temperatures (300 and 550 °C) on chemical, morphological, and structural properties of pristine and Au-doped ZnO nancomposites (Au@ZnO) was investigated. Transmission and scanning electron microscopy (TEM and SEM), as well as X-ray photoelectron spectroscopy (XPS), revealed the successful deposition of nanoscale gold on the surface of spherical and rod-like ZnO nanostructures, obtained after annealing at 300 and 550 °C, respectively. The pristine ZnO and Au@ZnO nanocomposites are proposed as active layer in chemiresistive gas sensors for low-cost processing. Gas-sensing measurements towards NO2 were collected at 300 °C, evaluating not only the Au-doping effect, but also the influence of the different ZnO nanostructures on the gas-sensing properties.
authors.affiliation: Department of Chemistry, Università degli Studi di Bari Aldo Moro, Bari, Italy; Department of Electrotechnics and Electronics, Politecnico di Bari, Bari, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Dilonardo
authors.affiliation: Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Technical Unit for Materials Technologies - Brindisi Research Center, Mesagne (BR), Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Penza
authors.affiliation: Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Technical Unit for Materials Technologies - Brindisi Research Center, Mesagne (BR), Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Alvisi
authors.affiliation: CNR-IFN Bari, Bari, Italy.
authors.forename: Cinzia
authors.initials: C
authors.lastname: Di Franco
authors.affiliation: Department of Chemistry, Università degli Studi di Bari Aldo Moro, Bari, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Palmisano
authors.affiliation: Department of Chemistry, Università degli Studi di Bari Aldo Moro, Bari, Italy.
authors.forename: Luisa
authors.initials: L
authors.lastname: Torsi
authors.affiliation: Department of Chemistry, Università degli Studi di Bari Aldo Moro, Bari, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Cioffi
keywords: Au-doped ZnO; NO2 gas sensor; ZnO nanostructures; chemiresistive gas sensor; electrosynthesis